WebRTC uses an external signalling channel to negotiate ICE candidates, codecs, and necessary information to establish a media communication. Once this is done, the visio/audio conference is P2P and encrypted from the caller to the callee: how is this not E2E? (Genuinely curious, not criticizing)
That is, if you're not using a TURN relay server, which is easy enough to know.
Maybe you meant that multi-party (one-to-many or many-to-many) calls are not E2E. Again I'm not too sure I understand: it is possible to have multi-party conf calls: each participants can encrypt its media stream and send it to the N-1 other participants. Obviously this costs a lot of CPU (for multiple encryption) and a lot of uplink because the same stream is sent N-1 times. But it is __possible__, and certainly viable with only 3 or 4 participants, provided people have a decent connection (WebRTC uses adapative bitrate streaming [0] to compensate for bandwith usage).
Then again, I know that generally, with WebRTC people would use MCU [1] when dealing with many-to-many conf calls, and then I agree it breaks E2E. But for the other mentioned cases, WebRTC is E2E, isn't it?
Again, I'm genuinely curious about this, not trying to criticize or undermine.
Thank!