FWIIW it doesn't really delete the data here either.

Citation: I deleted my account, asked friends if my side of old conversations was still there. It is.

That raises an interesting question: who owns a conversation?

I'm not at all sure how data protection laws, such as GDPR, do or should interact with online messaging systems. For instance, if you ask Google to remove all data they have on you on gmail, do they have to reach into the mailboxes of any other gmail users who have received mail from you and delete those messages?

Or do the recipients count as the ones who are storing that data, so if you want your data out of my mailbox you would have to ask me, not Google?

That would be a big violation of EU laws.

Maybe it depends on jurisdiction.

Yes it would be: but I used the Russian nuclear testing site as my address, so they may not apply GDPR to it.

Russian troll spotted? Maybe that's why Facebook "reactivated" the account so easily.

Yes, I'm sure most Russian trolls use the Russian nuclear test site as their home address when posting from Berkeley.