We have the same (or similar) problem with iOS 15. iOS 14.8 worked fine, but under iOS 15, WebRTC video and audio aren't getting delivered to the remote peers.
A fix that worked for us was to have the user turn off "WebRTC Platform UDP Sockets" in the iOS Safari -> Advanced -> Experimental Features.
We also experimented with the "VP9 Decoder", "VP9 SW Decoder on Battery", and "VP8 Decoder" experimental features, but no combination seemed to work.
schoolcoder
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