"I want my software to stay out of my way and only update when I say to" also me the moment an update releases for anything:

At least this is still you choosing when to update

yeah, I just thought it was funny that ive been checking literally daily since I switched to Linux.
- If you want you can setup automatic updates in kde settings. They will always stay out of your way and download in the background. They will install if you chose to click "update and shutdown" next time you shutdown or restart your computer.

It's choice vs force.

I like that on Linux I can install the updates and know that the ones that require a restart will just be ready the next time I restart at my leisure. And if I don't feel like restarting right away, it won't nag me about it and maybe just restart on its own if it decides I've put it off for too long.
And I can't believe my previous "solution" to that was to give ms even more money for win 10 pro (to get access to the paywalled settings) only to still feel like ms thought it was their computer that they allowed me to use.
- exactly my thoughts. I'm in control here but it also does stuff the way that makes sense on its own whenever I dont mess with it.
- And soon(tm) we'll have wayland session restore when we do restart!

I just want my software to leave me the fuck alone and update automatically. Why is this so difficult?

There's probably an option in your distro to automatically install updates, but it's annoying when that happens when you're in the middle of something or if they require restarts
- As much as I hate to praise Windows, that's why they have "update and shut down" when there are updates available.
Theres an option in Fedora KDE but it has never worked for me for some reason…?
- Same.

But it's such an excitement!

Automatic updates don't give you the pleasure to see what changed and update and test new features out

When you run sid and update some times 7 times in a day 😁

Restarting is good for a computer's health, right? I think my Kubuntu laptop is the only machine in my house that averages less than two weeks of uptime

yes, iirc the general advice is to restart like once a week. its not a huge deal if you wait a little longer (two is fine) its just a guideline.
My CachyOS (Arch) desktop gets rebooted somewhat often because it suggests I reboot after some upgrades. I guess it's kernel upgrades, but I'm not sure which do and don't trigger that recommendation. Nor do I really know how important it is lol.

@unknown12345 I want my software to be updated in the background but limited to using only 10% of any resource (bandwidth, CPU etc) while doing so.

I can always set it to automatic somehow, but I never saw those utilities offering a maximum download speed or CPU/Disk utilization setting in any distro.