I know the posts and content are shared between instances, but if an instance is shutting down it would be useful if there was a way to migrate your user data / identity to another instance.
I’d guess you would have to approve the move on both instances, I don’t know if this is feasible or not given how the fediverse / ActivityPub is structured.
I know there’s a way to do it on Mastodon, granted your posts don’t move but your profile, followers, and those you follow do move. So I assume something like that would be theoretically possible on Kbin/Lemmy l. Something like this would also be helpful if people just wanted to move to a different instance like if they decide to set up their own instance and move away from the default instance