So, I was born in the late 90's - I don't know if they still have "computer literacy" as a core course in schools these days, but they did when I was going through K-12 (or, well K-9.. once you were in high school they assumed you knew the basics of how to use a computer, and had more advance courses).
One of the very first things we learned about the internet is that once you put something on the internet, there is no way to take it back. At the time, uploading pictures to the "cloud" and such wasn't really a thing so we learnt this by using email: Once you've sent an email to someone, you cannot "unsend" it. You can kindly ask the other party to delete the copy of the email without opening it, but you cannot guarantee that the email wasn't saved on another computer, or saved somewhere else along the route between your computer and the receiver's computer. Clicking the send button was taught to us as "etching your letter into stone".
Because of this, I've always (or at least, as far as I can remember) made sure that anything I put on the internet, or even "put into digital form" (such as even writing something in a file on your computer - you can recover deleted files from a hard drive unless you really put in the effort to actually erase it... there is a huge difference between erasing a file, and marking it as "deleted") is something that I'm okay being tied with me forever. I'm sure if you looked hard enough, you could find me participating on message boards as a young teenager - and to that I just say "Oh well". Is some of it probably very cringe-inducing and embarrassing? I have no doubt.
(This is also why you should take extreme caution when talking about say, your friend, on the internet - if you post something about them on the internet, you're condemning them to this same exact thing)
Now funnily enough, as far as I understand the ActivityPub protocol, it is for all intents and purposes the exact same as email in this regard. Once you've sent something, there are no "take backs". All you can do is kindly ask others to delete their copy, and that comes with zero guarantees. If I had a mastodon server, and someone deletes their toot - I could take down my server and my server would never receive that delete request. Or, just simply change the source code of the Mastodon instance on my server to straight up ignore deletion requests.
Would it be nice for Lemmy to have a way to actually delete your content? Sure. But that's not technically feasible, and personally (as controversial as it may seem) I would rather Lemmy not try to give you the false sense that everything was completely gone forever. I'm not saying that you shouldn't be able to delete your account off a Lemmy instance, but it shouldn't come with an option that says "Check here to remove your data/media from all federated instances" because Lemmy/no one can promise that, and I really hate it when software (or really anyone/anything) attempts to make a promise in bad-faith knowing that they can't possibly ever uphold it.
Anyone who thinks Reddit is "better" than Lemmy in this regard probably doesn't realize that Reddit is making a claim they can't keep. The most obvious example of this is all of these subreddits that have gone dark? You can bring up most of their posts on the Wayback Machine or Google Cache. That would be the case regardless of whether they were set to private, or even if they were just straight up "deleted".
We really should not be setting the belief for people that there exists a way to completely nuke a piece of data off the internet, because you cannot make a guarantee of that being the case.
Not a guarantee, but a reasonable effort would be good.
Consider doxxing. It would be better if instances propagated delete requests to the fullest extent possible so that that information would be as hard as possible to find.
Propagating deletes is a request from one moderator to another moderator. If the 2nd moderator doesn't cooperate with the delete, then you have a moderation policy issue.
I don't really agree with this. The core behavior of Lemmy should be to make a reasonable effort to delete it, which as I've understood it doesn't really.
And you don't have to give people a false belief - the button shouldn't only say "Request removal of data from all Federated instances", but also add that "But keep in mind that it's not possible to enforce deletion from all instances in a Federated environment, and some instances may refuse to comply".
I think we should strive for privacy as much as possible, and by default the instances should comply. Sure, there's nothing stopping anyone from not complying, but that doesn't mean that we shouldn't at least attempt to do it.