Because that's a pipe dream.

First of all, you can't monetize it, and, unfortunately that is a non-starter. I can't see people throwing money at this, with the implications. Secondly, assume I want to contact the same anonymous person again. They have to somehow easily prove they have access to that username.

Even 4chan had a mechanism for this. Assuming you don't shield your IP, or you move between locations between, at least the service knows that, and that isn't anonymous.

A pre shared key off a one time pad only proves that someone has the same pad.

I think anonymity isn't achievable. Secure is more important. I talk to someone a lot, I want that secure. I don't really care if anyone knows we're talking, just whether they know the content.

Hosting your own metal somewhere helps with that. You'd obviously notice a warrant or whatever.

> Even if you create a throwaway email account somewhere, it'll often be traceable back to you somehow.

I'm surprised to hear you say this considering your completely opposite stance in response to a comment of mine. I don't see how a throwaway email is any less anonymous than a username. In fact, I see it as more anonymous since I can generate these on the fly whereas I can't do this with usernames.

i'm really glad that they're moving away from phone number as identity, and hopefully to fully anonymous, which they've rightly been criticized about up until this announcement.