I get that this is a new paradigm of “spatial computing” where your environment itself is essentially the new “desktop”. But no one who brings up “MacOS” is really talking about that.
Again, show me a number of people who are confusing this. Simply saying "you can run multiple monitors" doesn't mean they are referring to mirrored Mac os displays.
If I run a 3 monitor setup on my Mac, and on one I run Safari, on one I run Numbers, and on one I run Final Cut Pro...I can absolutely run that same setup on the AVP. And, I wouldn't even NEED to be mirroring my mac.