

Pretty sure you still need a phone number for an account, though - the usernames are just for sharing your contact with other people.
Most peoples’ phone numbers are easily linked to their identity. Which means the government knows who’s using Signal.
Usernames are definitely an improvement, but this is a fundamental limitation in Signal’s design.
So they could have replaced it with, like, email verification or something, but they instead stuck to the design that lets governments identify all users?
<Insert rampant and unfounded speculation about FBI compromise here>