First, it is a mistake to call these usernames. Second, it's a big mistake because this is a cool feature. It's interesting to compare this feature to Session,

First, it is a mistake to call these usernames. Second, it's a big mistake because this is a cool feature. It's interesting to compare this feature to Session, where you also have randomized identifiers, but they identify you globally, and there's no way to give someone a handle to you that isn't linkable to other conversations. It sounds like Signal now offers that, which is actually the first time I've been intrigued by Signal.