And yeah, as others point out, this is Apples to oranges. x86 desktops are great at some things, M2 Ultras are great at others, and the overlap that really matters is pretty small... Like, you have to be crazy to buy an M SoC for gaming, or buy a Nvidia GPU for workloads that won't fit in VRAM.
I imagine that in the future, something like Steam will wrap this functionality to provide the ability to run the whole library under the toolkit. And individually-published games will do the same so they install and run with a more consumer-friendly experience.
I have seen the demos, but I am skeptical of the actual practicality or value proposition until a 3rd party publishes some frametime benchmarks, and games out in the wild get battle tested.