Short comment: even we can't follow on the twists and turns on this topic from Apple. Before there was Catalyst -- developer.apple.com/mac-catalyst/ -- which we never got working. Then there is this new thing -- "Show Mac (Designed for iPhone & iPad) Destination" -- which may be Catalyst, or might not be Catalyst. The main driver NOW is the M1 chip, whereas before Catalyst was also for Intel architectures.
Anyway, yeah, the thing will eventually run on Mac too. In fact, we've run it on Mac, but until we have a production-ready testing and deploy strategy, we're holding off.
I realize this comment might be more confusing than elucidating, but... info!