you can’t move that account somewhere else.
That means you can migrate between servers and keep all your friends and followers, something that’s currently not possible in the Fediverse.
It absolutely is possible to move accounts between instances on the fediverse. I’ve done it multiple times.
It does have some quirks tho. Posts aren’t migrated to your new account. (Some fedi software lets you migrate posts, but from what I hear it’s kinda jank).
It’s not seamless, but the option is there, and you won’t lose any friends or followers (unless they’re defederated or something)
Bluesky accounts seem like they’ll be more portable than fediverse accounts but I don’t know much about it
You’re not really moving your account - you’re just migrating your followers over to the new one. If people try to reach you at the old handle they won’t get through, like a dead email address.
That said, I don’t really think this is such a big problem. The reason the AT protocol was invented is because they wanted to do their own thing rather than adhering to standards.