What technologies were ubiquitous ten years ago and are much less common now?

ITT: People not realizing 10 years ago was nearly the end of 2015 and listing technologies that were popular 20+ years ago.

2015 still feels like a date from the future to me

I'd say audio CDs, but those have been back on the upward trend since streaming and download services started getting hostile and people started wising up to that hostility, in other words, people want to own their music again and so started buying CDs again recently vs. having a streaming or download service randomly yank content they paid for from their libraries.

Cd roms. Network ports on laptops

Pay phones, Public water fountains, Coffee grinders in grocery stores, all the hundreds of gadgets that our smart phones replaced, Tons of random accessories for everything were all over stores and eBay but sadly all gone now.

all the hundreds of gadgets that our smart phones replaced
In 2015, at least in Canada, smart phones were already ubiquitous.
Interesting point about the grinders, I'm just realising I haven't seen any in forever.
- The grinder thing is because Keurig K-Cups came out, and the entire industry shifted towards selling those instead.
Oh yeah, coffee grinders in grocery stores. I rarely see those anymore, but they used to be everywhere.

I'll take the opposite view... what technologies are ubiquitous today that will be irrelevant in a few years?

Smartwatches. Nobody needs this shit, they're mostly just toys for fat people who want to "monitor their health", and for gadget-goofs that need everything shiny, new and overpriced, regardless of the actual utility in their lives.

Yeah nah.
People (normal people) like having their messages, facebook comments, whatever else coming up somewhere even more accessible than their phone in their pocket.
- The transition from pocket watches to wrist watches was for similar reasons, although it took a (first) world war for the convenience to be fully appreciated.
Love my smart watch
I go jogging and leave my big bulky phone behind. I can still track my jog, listen to music, and check my heart rate, but at 1/20th the weight.
I loved having a smartwatch, for the brief period of time I had one. They fell to (IMO) the pitfalls of being annoying to charge and being tied to massive smartphone walled gardens. After a few years my smartwatch couldn't even hold a charge through a single day, and had lost support from the manufacturer anyway, and was hard to keep synced with my phone, and eventually the hassle became too much for it to be worth it.
But if we had a standard API for wearables that smartphone companies adhered to, and I didn't have to charge it every night, I would love to have another smartwatch. They're so convenient.

Optical disks. It was almost a necessity on laptop to have an optical drive, now there's maybe one or two models out there that comes with one.

Even 10 years ago, disc drives seemed to be out of fashion. But if you laptop was 5 years old, it likely have one anyways.
- I used a MacBook for 10 years that was one of the first models to come without a disc drive, it was a 2013 model.
  I recall it being a bit ahead of the curve at the time, but it was a pretty fast curve before you really couldn't find a laptop with a disc drive anymore.

Search engines that work.

Even when you get to the actual website results you now have to wade through the AI slop sites
Oh god, yes.
I could type in a question ten years ago and could usually get an answer in the first page or so.
I asked a question yesterday (about floor tiling) and got "Tiles? You want tiles? We've got tiles! Get your tiles here!"
"No, I want an answer about flooring."
"FLOORING? You want flooring? We've got flooring! Get your flooring here!"
"Ok, fucking hell. Ok how do I join 2 types of substrate together..."
"MUTHERFUCKING, substrate? You want substrate? We've got..."
Then I gave up looking. Maybe it was always like this and I used to be more tenacious looking for answers.
For that matter, it felt like a peak for the rest of the internet, and everybody loved silicon valley and wanted to be Steve Jobs. Then the enshittification started.

Maybe 1/100 people I see using headphones have wired headphones, certainly wasn't the case 10 years ago. Bluetooth technology and quality has come a long way.

I'd still have wires IF MY PHONE HAD A PLACE TO PLUG THEM IN.
- I refuse to buy a phone without a headphone jack. I'm not sure if I even have a choice anymore tbh... Really I only use my phone for music and text/call. A dandy map if I need one, but not usually.
- I do like my AirPods, but I'm still pissed off that the duopoly killed the headphone jack. Give me back my headphone jack!!
I could NOT be bothered with charging headphones daily.
- My Marshall on-ears have a battery life of like 80 hours or so...
- A decent set of headphones will have an effectively all-day battery, and most people probably aren't listening to their headphones for 8+ hours a day.
  I've had my headphones for about 7 years now and they still last for several hours on a single charge, and they support fast charging. If they're at 0%, I can plug them in for 10 minutes and they'll have about 2 hours worth of charge. I charge them maybe once a week with casual use.
- They usually charge themselves in their case (small pods) or have big batteries (over ear). I use my pods probably 8 hours a day, and just need to charge the case once or twice a week.

Office phones.

Sounds about right. Last time I had an office phone at my desk was 2021.
- I have an office phone, which is at least 10 years old at this point. One call every couple of months and it is spam.
I had to fill out the number for my HR department on some paperwork. Tried to look it up. My large employer doesn't have a phone number at all for any department - even HQ.
Hell - I question if home phones are really hanging in there.
- Our home phone is an extra line on the cell plan. That phone sits at home most of the time, and is a games phone for when kids come over with parents.

Ubiquitous might be a stretch for 2015, but DVI cables come to mind.

I'm stilling rocking my GTX 1080 I bought in 2017, and when I had to switch the DVI cable for my smaller monitor, I had some fun looking for the thing. Partly because of how uncommon they've become... partly because there's a lot of them DVI types and I think I bought the wrong one the first time.
while a straight dvi-d to dvi-d cable is quite uncommon to need today, i have used a bunch of hdmi to dvi-d adapter cables the last couple months to hook up new desktops to older displays that had vga and dvi-d inputs.
- You’re giving me flashbacks to all the different DVI standards, and whatever you were plugging in never matched the type you had.
- I have a number of older monitors hooked up to two GPUs and use just about every modern interface and adapter to make it all work. VGA, HDMI, DVI, DisplayPort. Technically it may not be the best and some monitors may refresh slower or something, but it works for me.

Dedicated GPS unit in your car

My parents gave me a GPS unit for my car about 20 years ago and I used it for the longest time. It was great help when driving in cities and big towns or locations I had never gone to before. We used it all the time and I think I updated the maps ... I think it was a Garmin device ... I think I updated the maps 2 or 3 times over the years. Then it went unsupported but I kept using it for the longest time.

Then I started buying better smartphones and my phone just eventually replaced the GPS unit.

I still have it and it still works and the battery on it is still good ... I just don't need it any more and the maps are about 10-15 years out of date.

I have an old garmin gps in my car. Use it all the time combined with a phone. The garmin doesn’t need cell signal so it works everywhere. Funny when going places where the street didn’t exist back then, but it’s kind of cool to see how the city grows. We mainly use it as a backup. It’s also louder than the phone talking and easier to understand.
- You can download maps on your phone, so you can use it in areas without service.
  Used that when I went to the state's and didn't pay for roaming/data. Just downloaded Oregon/Washington.
I can say the same about my ipod. I used it everyday for the longest time until I realized I can put a 126gb micro sd card in my phone which is more than double what my ipod had. Now it's sitting in a box somewhere in my closet. Probably still works too.
- It's a shame modern phones have been losing both micro SD card slots and headphone jacks and often don't have a substantial amount of storage. Still better than carrying multiple devices, however.
True yeah.. Garmin devices were so revolutionary for driving when they came out. Then phones with Google maps came along and that was easier

Independent portable media players. Most of those functions have been susumed by phones.

Which makes me frustrated that all the manufacturers have gotten too cheap to toss a miniscule DAC and headphone jack in phones anymore.
- Headphone jack and micro SD cards and the biggest losses for me.
- I don't think it's about them being cheap, it's that they want to sell you the matching wireless headset
The functions of this player have not been subsumed into a phone.
- That’s pretty nifty! I’ve been looking at a personal AMFM radio/MP3 player recently, but I really like the CD ripping function of that one.
- It has nubs

disk players

I miss when laptop computers usually had disk players
- USB external optical-disc players are available to plug into any computer.

URL shorteners, AMP? Micro USB?

Edit:

Thinking of things that weren’t made obsolete but just unprofitable…

Physical menus at restaurants, useful search results, human support staff, non-subscription software, open APIs, useful product reviews

I almost never came across a restaurant without physical menus here in Germany🤔
I hate with a burning passion QR code scan menus.
- QR codes are great! They let hackers replace it with their own so they can infect your phone 🫠.
  Bonus points if they offer an app to download and really get at stealing your data. /s
- I saw on Kitchen Nightmares one time where the QR code pointed to http://localhost/ haha
- I don't have a smartphone, so QR code menus mean I don't eat there.

Headphone jacks. They certainly still exist but every device I owned that made sounds had one in 2015, no longer the case

For PC gaming and any sort of production/studio environment they're still ubiquitous. Although yeah, not a daily driver for the public nowadays.

Plasma TVs, DVRs, DVD players

Adding onto this: 3D TVs
- The one technology was obsolete before I could buy it, though when I first bought an Oculus Quest I tried ripping 3D Blu-rays and realized ~12 fps per eye is pretty shit quality anyway.
- Speaking of things that went nowhere, but the manufacturers thought they were the next big thing...
- You bought the wrong tv silly head
Plasma TV
Now that's a name I've not heard in a long time. A long time...

I don't eat at QR code restaurants.

If you don't have a menu, I don't pay.

If you come to Taiwan you will starve.
I much prefer some of the QR code restaurants we have in my city. I don't want a waiter hassling me throughout my meal.

USB drives, dvd/blu ray.

I'll die before I let go of my 5 USB drives (yes I use them all)
- I bought a 5-pack of 8GB USB drives for making live USBs, many years ago it feels like, and have somehow managed to hold onto all of them. I tend to use Green and Black the most for file transfers and they have started to fail pretty regularly but I can't throw them out, they're a family. Funnily enough Purple, the one that got assigned "Permanent Ubuntu Live USB" duty and has seen more than its share of writes, is still rock solid.
- i had a usb from 2016ish-19, so i was using a university school computers for writing resumes and applying to job sites, plus, and sneaking in a game installer, since the school computer blocked it that the time the usb bypasses it.

They weren't quite ubiquitous anymore, but looking for a payphone wasn't a sign of someone being a time traveler. The last one near me hung on until a couple years ago.

There's a payphone by one of the elementary schools here. I wonder if it's more likely that a kid without a cellphone is more likely to use it?
- Actual prepubescent children, in my experience, no longer recognise something without a touchscreen as a phone.
- Here in Australia, they are all free now. I presume the phone company realised nobody was using them and preferred to keep them as free billboard spaces.

Portable handhelds, I mean form factors like the PSP and Nintendo DS. The downside of the console/handheld convergence is that the handhelds need pretty big screens.

Tablets? Those seem to have really fallen out of fashion and have been replaced with regular smartphones becoming quite a lot bigger.

I've encountered a ton older folks using them around here, for example reading books or even just using them for bank stuff instead of a computer or a phone. The bigger screen makes them a lot easier to use, especially if your eyesight isn't as good. I guess that tracks with "fallen out of fashion" though
I recently got a tablet so I could take handwritten notes during meetings. I thought I'd use it for a bunch of other stuff but I do not.
Not to mention, the ~~OCR handwriting recognition~~ my handwriting is really bad.
I like my tablet for ancestry research and not much else. But I think maybe still good for artists?
I see them often used in universities, maybe not as much elsewhere as ten years ago but still a regular occurrence

CD's & Mp3 players

4G cellphones.

My phone supports 5G, but I never got to try it yet because I'd have to pay extra to my provider (Austria, Magenta (T-Mobile)). Fuck that, 4G is fine by me. Besides, I could still use 3G and aven 2G, although that'd be a bit insane.
But 5G phones still comes with 4G antennas and 4G cell towers are still being used to cover areas 5G cant reach (since 5G hass less range). I don't even have a steady 5G connection where I live lol (its not even that rural, I live in a US City ffs).
I would rather say 3G cellphones.
LTE is still widely in use today, while being mainly common in higher-end devices in 2015.
3G/UMTS on the other hand still was the mainly used one in 2015, also because of pricing, while 3G networks are completely switched off by now.