I think what we’re seeing here isnt Valve messing up but rather the middle east conflict expanded to cyberspace and spilling over to impact civilians. Look at the timing and affected countries. China isnt also exactly known for free internet.

WebRTC works as fallback. WebRTC is encrypted and cant be used for much else.

STUN in the otherhand is unencrypted and the protocol itself can be used for DDoS reflection/amplification. I would not be surprised if this is somehow weaponized and/or blocked/analyzed in real time that then breaks the connectivity.

STUN/TURN is basically icanhazip for WebRTC. STUN gives you your public IP:port. TURN is the same, but the returned IP:port is the one that had been dynamically allocated to you at time of querying, rather than the actual ones.

WebRTC clients take that STUN/TURN response and send to peers through out-of-band, through e.g. a lobby server chat mechanism, to set up the connection. This allows NAT table entries to be created as if they are outbound connection at both ends.

You can't make P2P connection with STUN/TURN alone. STUN/TURN is just a tool required for WebRTC.

I think you have that backwards, WebRTC doesn't work, and STUN does.

> impact regular people

I'm sure it was unintentional, but this phrase implies a pretty ugly sentiment