In Matrix all u need is username, email and password and ur ready to go. Homeserver is configured automatically to matrix.org (which is a problem, but nvm)
The downside of matrix is complexity of choosing a client though. And in general understanding a concept of matrix is not easy for regilar person.
For example u can say: “Im on Signal”, but u cant say: “im on FluffyChat”, or Element whatever, it sounds wrong, cuz these are only the clients and everything is working on matrix. But the regular person needs an object: telegram, signal, whatsapp - these all are just single entities. On the other hand u have matrix with clients, homeservers, spaces and all of this complexity, and that is not easy to understand.
Yeah, i hope in future this problem will be resolved.
Why everybody is talking about signal? Isnt a matrix also a good alternative? It requires no phone number + has almost the same feature set. For chatting with family and friend it scales enough good. It is fully open source.