It would be nice to have a server that supported arbitrary domains. Perhaps https://jointakahe.org/ would suit?

OTOH, eg. (not an advertisement, just the first search result) masto.host offers managed Mastodon hosting for $6/month, which is on par with eg. Fastmail or Proton's base non-free plan.

Unless I'm missing something, that's exactly the same.

If you're using someone else's email domain (like, eg. gmail.com), you cannot migrate to another provider. If you use your own domain, you can change who is hosting it.

Like email, there are plenty of Mastodon hosting companies. You can use your own domain, and migrate between them at will. If you use eg. mastodon.social, you can even migrate in most circumstances (but not if the instance vanishes).

How is ActivityPub instance migration worse than switching email providers?

So run your own instance.

Using someone else’s instance is just outsourcing your decisions.

Other people might be ok with or even enthusiastic about that, but that shouldn’t be your problem.

I’ve seen the Internet from the 1980’s until today. It has always had people exploring gender identities and public sharing of neuroses. Mostly nerds, though.