Understood. And thanks! I wish I could use your answer as an excuse to finally get an Apple-silicon machine for my work :D

Disagree. I have no idea why do you figure out that a 2-dimensional view to project 3D graphics is not something you would want to do in Vision Pro - after all, being able to play regular games in a really, really big "screen" inside a VR/AR headset is one of many applications of VR/AR. As a matter of fact, I'm in need of such a thing myself - my project allows the user to play a game in immersive and non-immersive mode. Would be nice if Apple allowed Metal to render to VisionOS windows...

https://download.developer.apple.com/Developer_Tools/Xcode_15_beta_8/Xcode_15_beta_8.xip

Maybe I should clarify. The reference page for precisely that, is this: https://developer.apple.com/documentation/compositorservices/drawing_fully_immersive_content_using_metal (I have a hobby project that ports an old game to VisionOS using this)