As far as I know, Mastodon didn't really set out to solve that particular problem. But it does seem like ATProto did, as it seems a lot easier to move around in ATProto than Mastodon (and ActivityPub in general).
You're complaining that moving away from a PDS means you have to let that PDS know you're moving away? Do you understand what you're actually complaining about, or I the one who misunderstand what you're complaining about?
