I don't agree with that. Both sides are acting as a server and a client, connecting via a onion service to either parties rendezvous. And then when you include the fact that you can become a relay, that is clearly self hosting a server in a pure sense.
There are no exit nodes involved in onion services. It all stays within the network.
Happy to contribute! So, currently (only while in the app for now) you can activate the mic with a double pressdown on volume if the setting is enabled.
My attempts to trigger the mic while outside the app came with a few unwanted side affects so I removed it for now until I find a solid way to do that.