Fediverse

Your ID is stuck on one server, even if you can post messages on other servers. One server must be your "home" server. Unfortunately, this means that if you ever want to start using kbin all the time time instead of just posting messages to it, you'll have to register an account there. I don't think lemmy or kbin offer a way of migrating your account right now, so you would have to just start a new account on kbin.

What protects/ prevents some one from making a u/fomo_erotic on kbin? Anything?

Nothing prevents that from happening. However, your name is not just u/fomo_erotic, it's fomo_erotic@lemmy.ml. The "@lemmy.ml" part at the end is important, it's part of your full username. If you hover over my name, you'll see that it ends with @kbin.social.

This is the same as how email addresses work -- someone can be john_doe@gmail.com, and someone else can register john_doe@outlook.com, and the first John Doe doesn't really have any way of stopping that. John's contacts need to know that he has a Gmail address, not an Outlook address.

Lemmy hides the @lemmy.ml part at the end unless you hover over the username, and I wish it always showed the full thing, because hiding it makes it easier to impersonate people. That isn't really a big problem right now, though, since Lemmy is still too small to have a problem with impersonation accounts. But imagine if you got an email and it just said "from john_doe," no @gmail.com after it. Hopefully Lemmy changes that soon.

If I'm concerned about other people in the fedi being 'me' should I get fomo on those ids?

I don't think it's worth worrying about that. Plus, it won't even be possible to worry about it eventually. While there are only a few Lemmy-like sites right now, eventually, like email, there could be thousands.