It's especially problematic as long as Mastodon doesn't have a way to migrate your post and reply history to a new instance. Only followers are migrated. And that's if the transition is orderly, you weren't banned and the instance wasn't shut down by the FBI.
Discussion
https://codeberg.org/fediverse/fep/src/branch/main/fep/ef61/fep-ef61.md
But judging by feature adoption speed we won't see this in Mastodon and Pleroma for years.