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.
Usernames exist for a reason, especially in chat apps. Not having usernames is only going to severely limit your target demographic. And if nobody uses your app does it's benefits even matter?
A Messaging app is made for communication. The ideal dream is a messaging app that is both easy to communicate with, and respect privacy. If a messaging app cannot be used for a common messaging use case, like dating. It's not going to work as a general messaging app