GDPR is not a valid use case In this particular discussion since policies or rules should handle that. Not the services it self.

Side note:
Still unknown how this will work out in reality. Increased awareness of privacy, yes and implemented solutions, yes. But we have too many corner cases in the world yet

Just take tmo as an example. Do I have the right to be forgotten. Possibly. Might be easy to remove an account. But what about all post where the user was quoted?