None of that addresses the need for there to be a platform level feature that does all that. None of what you described comes free with hand tracking.
Sure, it can track your hands. Maybe it can track the things in your hands and use them as “controllers” (once again, that would actually require Apple to provide that feature). But it certainly wouldn’t by default say “oh this user is using an Apple Watch in their right hand so whenever I need to vibrate that hand I’ll vibrate the watch”. That is fully and 100% something that Apple would need to provide. And given their stance of “hands are enough”, why would they ever provide those features out of the box? With no first party accessories to use it?
And, once again, this has nothing to do with Beat Saber being an exclusive or not. That is the topic of this thread, not this diatribe that will only ever be pure speculation for the next year and a half.
My point is many developer will find some unique ways to find some new applications of hand tracking combined with other things.
Apple will provide hand tracking data for visionOS in latest ARKit - I watched the WWDC session.
Even currently if you play Nintendo switch nothing stops users to hold left joycon in right hand - you still have to do onboarding. But with hand tracking and motion sensor data it's very easy to detect which hand holds which device with some onboarding/tutorial. Sure you don't get it out of the box but there were lots of cases for iphone where people used many workaround and tricks to implement feature that was not there. Flashlight Apps in first gen phones using screen comes to mind.
I believe you can even support PS Move with 3rd party SDL library (official apple game controllers API support only MFI controllers + xbox one controller + PS4/5 controllers and Switch Joycons (both left and right)
Sure, it can track your hands. Maybe it can track the things in your hands and use them as “controllers” (once again, that would actually require Apple to provide that feature). But it certainly wouldn’t by default say “oh this user is using an Apple Watch in their right hand so whenever I need to vibrate that hand I’ll vibrate the watch”. That is fully and 100% something that Apple would need to provide. And given their stance of “hands are enough”, why would they ever provide those features out of the box? With no first party accessories to use it?
And, once again, this has nothing to do with Beat Saber being an exclusive or not. That is the topic of this thread, not this diatribe that will only ever be pure speculation for the next year and a half.