It might suck for handoff and be fiddly with the iphone camera etc. Shareplay is mystifying, the whole UI is cryptic.
But the audio signal processing chain is wild AF. You can blast movies, YouTube etc out of a full theater speaker setup and still simultaneously have excellent conversational quality between parties. The echo cancellation is so thoroughly complete that the other side can’t even hear that your playing anything most of the time.
The iPhone itself always was pretty amazing at this but your “continuity camera” microphone is usually much further away and also Apple isn’t in control of your home theater audio.
Hat’s off to the engineers who worked on this undersung capability.
Really there’s a lot of reasons to say it’s bad and half baked. But the bones of it, clear two way communication, are not easy to do and I just want to praise them for that.