> Also, they have intentionally excluded the option for clients to connect to alternate servers.
Since Signal doesn't federate, if you switched your client to an alternate server you would be unable to communicate with the 99.9% of people out there using the official Signal server. Signal isn't going to give a UI option that is certain to cause frustration and bafflement for the vast majority of users. Those wanting to use an alternate server are probably a small nerd niche who already know how to fork the client.
Since Signal doesn't federate, if you switched your client to an alternate server you would be unable to communicate with the 99.9% of people out there using the official Signal server. Signal isn't going to give a UI option that is certain to cause frustration and bafflement for the vast majority of users. Those wanting to use an alternate server are probably a small nerd niche who already know how to fork the client.