MartianSands , 10 hours ago (edited 6 hours ago)

That’s going to be a problem whatever solution you come up with, because of the federated nature of the lemmy system.

There’s no central authority to hand out usernames, so if two people sign up to different instances with the same username, any design which didn’t attach instance name to each username would fail. The only way around it would be for each instance to contact every other instance which exists, including the ones which haven’t federated yet, and negotiate ownership of the new username, and that’s just not possible