The state of nomadic identity on the Fediverse: it exists.
But there's a fundamental problem with it.
1. Apps that support nomadic identity are easy to use as far as nomadic identity is concerned, not so easy with everything else
2. The most popular apps (like Mastodon) don't support nomadic identity, and they tend to be the easier Fediverse apps to use -- though not so easy for identity management
(A request: Please Google "nomadic identity" if you don't know what this is.)