Signal is all about private communication, and now they’re making it even more private by changing the default setting so your phone number is no longer visible to everyone in the app. You can now create a unique username to connect with others without sharing your phone number. There are also new privacy settings to control who can find you by your phone number on Signal. These features are optional, and you have full control over your privacy settings. Usernames are not visible to others unless you share them, ensuring your communication stays private. The changes are in beta, but will be available for everyone soon.
https://signal.org/blog/phone-number-privacy-usernames/