I know Twitter does this. Also saw someone mention Facebook asked for the same when they tried to delete their account. It's a mad mad world out there.

That might be consequence if GDPR: they need legal proof of the legitimacy of the request and of its thorough execution.

Just as you can’t really “unsee”, you can’t fully delete data once you’re exposed to it. Something documenting its previous existence will always remain

Facebook for sure. I don't know about the others.

I had to create a FB account for college, and somehow my account was suspicious according to them. They locked it and said that I needed to provide a picture of my national ID in order to unlock it.

I was baffled and just created another account to be honest.

Linkedin