> It's a migration for the future, not a migration of your past content - understandable because that past content likely has references from other instances and pushing those changes across would be a heavy operation, unreliable, and probably fraught with potential security problems.

Yes of course I'm getting the technical and conceptual difficulties as a developer, but it's awful UX. It's a real deal breaker once you discover it. You cannot use Mastodon as your primary content database anymore.