SimpleX Chat - a private and encrypted messenger without any user IDs (not even random ones)! Make a private connection via link / QR code to send messages and make calls.
SimpleX Chat is an instant messenger that is decentralized and doesn't depend on any unique identifiers such as phone numbers or usernames. Users of SimpleX Chat can scan a QR code or click an invite link to participate in group conversations.
-privacyguides.org
It's clearly proving to be the most innovative technology when it comes to decentralized communication, in my opinion.
Interesting project, but last time I tried it was battery hungry, and having made quite an effort to get some of my contacts on Signal, I don't see it happen to get them all on SimpleXChat. And Signal Stickers make Signal more attractive for some.