The beauty of the fediverse is that the last panel can’t happen.
We control our own instances. There’s no world where admins wouldn’t defederate from any Facebook attempt to barge in.
Maybe a few larger instances sell out, but users hold the power here now. If an admin betrays our trust, we’ll just make a new instance.
Not at the moment.
There’s an issue for it on GitHub, but it’s unlikely to be implemented: https://github.com/LemmyNet/lemmy/issues/2397