I think a federated system is probably possible. If Matrix comes out with a killer server and client combo in the next few years, it could take off and really w

I think a federated system is probably possible. If Matrix comes out with a killer server and client combo in the next few years, it could take off and really work. But I think if too many server implementations are created, they will end up in a state where its not possible to add new features anymore because a large percent of the user base won't be able to use them because their server implementation does not support them. Having compatibility between systems like between discord and telegram is just going to be a nightmare no matter what you do since they both want to decide on their own what the features should be.