“Arguably worse for privacy than Reddit”

This poster clearly has some sort of vendetta against Lemmy and/or its creators with the comments on politics, etc.

Reddit takes your activity and packages/sells your data to advertisers. Lemmy does not. To say Lemmy is worse than Reddit for privacy is just not true.

I’d take that post with a hefty grain of salt.

Just like on reddit, treat everything here as public. Do not post things that you want to be private to either site; this goes for literally any website you don’t own.

It reads like someone has just discovered that if you toss out public data on the public internet via federation it becomes public and out of your direct control.

That’s how all federated services basically work: once it is relayed to someone else’s server, there’s essentially nothing you can do to force deletion.

Easy example: if you send me an email, but delete it from your sent messages, did you delete the message I got?

Any claims made about privacy on a social media site, especially ones run by private companies or individuals, should be met with extreme skepticism. The reality of privacy on the internet is that it is not something you can get by picking a different service, it is something you must constantly maintain with vigilance and an up to date understanding of infosec practices.