It's there for a reason. You can't easily create a spam waves if you need a phone number to create an account. And they added usernames now, so you don't need to share your phone number with people you want to talk to. It's just there to create an account and can be hidden after that.
There is Session, that uses UUIDs for names with no phone number requirement, which is basically a fork of Signal with decentralized Loki on top of it.
How I Got a Truly Anonymous XMPP Account:
Sorry, it's a cheap joke, but it still baffles me that Signal requires a phone number, so I felt I had to post it :)
Of course, this is not XMPP-specific either, just my protocol of choice, there are many other open alternatives that also offer such functionality.
And - gasp! - you can do it from your computer directly! No Android emulators, no inconvenient command-line client!
It's there for a reason. You can't easily create a spam waves if you need a phone number to create an account. And they added usernames now, so you don't need to share your phone number with people you want to talk to. It's just there to create an account and can be hidden after that.
There is Session, that uses UUIDs for names with no phone number requirement, which is basically a fork of Signal with decentralized Loki on top of it.