I'm still fairly optimistic about ActivityPub since a lot of the problems there are in theory solvable, but we'll see.
* it has by far the highest-quality conversations I've ever seen
* no right-wing freaks disparaging trans people in the replies to everything
ActivityPub does have a migration story -- people move servers all the time. But it's not as good as it could be, and there are rough edges.
Correct me if I'm wrong (and in this case I would love to be), but you can migrate your account to a new server, but you have to create a new identity (ie profile URI) on that server. This would be fairly easily solved by servers allowing users to bring their own domain names. In the age of Let's Encrypt it's much easier to manage certs for many domains. They've known about this for 6+ years[0]. The fact it's not a high priority is concerning.
Fortunately this isn't an inherent limitation of ActivityPub, and I'm hopeful we'll see implementations with better custom domain support in the future.
Oh thank god I'm not crazy and not the only one. I genuinely don't understand what either broke these people or what propaganda/troll bot network is responsible but the replies randomly ranting about trans people in threads that neither involve an actual trans person in the conversation nor are about anything even remotely related to lgbt issues is baffling.
I mean, they most certainly are on the Fediverse/Mastodon, but they are also almost certainly not federated with your instance.