I'm not saying that "you can't make this complaint because you made an account here". I'm saying "only an idiot can make this complaint because this is how all distributed systems work without exception". There isn't a single system out there that is connected to anything outside of itself that isn't susceptible at some level or another to exactly what the OP is complaining about.

This includes the router you have between you and the Internet at large.

EVERY distributed system retains copies somewhere for some duration. And ANY of them can be (pretty trivially) modified to just retain everything for as long as there is storage to hold it. If you want privacy you're going to need end-to-end cryptography, but that means no discussion sites like this.

So my objection to the OP's complaint is that it's just stupid. Because it applies to literally every piece of technology they likely use to post the complaint, but for some reason it's Lemmy that's being singled out.