@atomicpoet Does it matter? If the underlying protocols are architected for federation and easy migration then any instances that go bad won't last long.
I do see a model like SMTP e-mail becoming a thing where technically anyone can federate, but it becomes increasingly hard for non well-resourced players to provide the necessary abuse management to play effectively.
@rob The instances that have gone bad have lasted for a very long time.
Technology does not replace human moderation.