It's easy to offer features when you're allowing yourself to keep track of everyone who's talking to everyone else in a serverside database.
Re:Secure messengers in war time
by kitkat_new on Wednesday March 02, 2022 @10:22AM
(#30528349)
Conceptually, there is nothing that prevents you to put the server on the phone, and employ store & forward nodes.
See what people are working on regarding Matrix: https://matrix.org/blog/2020/06/02/introducing-p-2-p-matrix
Signal could undoubtedly offer more features. Lacking granular permissions in group chats, for example, is not something I read as being "by-design". The phone number one is by-design, but I do not really agree it is a good security choice.