With regards to live video broadcasting (as opposed to VoIP), I'd be hard pressed to call WebRTC a technology that works well. WebRTC for one-to-many feeds is poor for live video for many reasons. For ABR scenarios, there's no concept of having multiple renditions, so if one subscriber is having trouble receiving video from a publisher, the subscriber reduces the bitrate of that publishers feed for all receivers (unless you take out that capability in its entirety, see the FTL protocol created by the team at Mixer). In addition to this, WebRTC has no real concept of segments, which makes building a CDN to reduce load and latency at an endpoint is a difficult proposition at best.

LLHLS is darn good, but it's not as good as WebRTC-powered technologies have shown from a latency perspective. Whether that's required for particular use cases is really pertinent to the case. For non-interactive feeds, it's not really a value add.

That said, the biggest quality improvements MoQ has are how it recovers from a poor connection issue, which happens frequently even on the best of consumer networks and Internet connections, let alone on poorer quality WiFi and cellular networks.