Self-hosted servers are usually pretty identifiable is my problem with this. Signal can afford the legal teams to fight court orders and has adequate infrastructure in place for plausible deniability.

This depends on threat model. I'd say use your own servers to contact family and friends the government knows you know, especially if you get them on that server too. All they'll know is you all talked to each other over that server, but not who spoke to who.

For people who don't want associated with you, use a public server. Whether that be one hosted by the simplex devs, or someone else. Alternatively you could run one over TOR.

I'm not sure if there's a way to set this up in the client, but based on my understanding of the protocol, it should be technically possible to allow the user to set specific servers per contact as well.

A vast vast majority of lusers won't have the resources or skillsets needed to properly set something up.

You could say the same thing about the fediverse, and yet here we are. Those of us who are lazy or are looking for pseudonymity use public servers. The rest host their own.

Turns out you only need a small minority of server admins to handle the need of the network. Who knew?