WebRTC should be capable of multicast, so nobody should be having to send X-1 streams for X users. I say should because it's incredibly hard to find out which parts the the WebRTC spec browsers actually implement. I just found an article from Mozilla from 2018 that just blithely mentions in passing some nebulous future date "when WebRTC is (hopefully) enhanced to support multi-user conversations." WTF have I been doing with more than 2 people in a WebRTC session for the last 5 years? What the hell has been going on in WebRTC for the last 9!?