Assuming the Apple headset has similar features and quality as Varjo XR-3 ($5,995.00) + better ergonomics, I will definitely consider buying it for that price.
Apple is more leaning towards AR than VR - a device useful for prolonged usage like ~10 hrs a day. So, chances of a headgear are very low. It'll be more like RayBan glasses offered by FB or spectacles.
the oculus quest 2 runs android and costs ~$500. Apples native code and ability to code for a a single platform would enable them to get the same experience at reduced specs.
I’d wager the current iPhones chip is more than capable to exceed an oculus quest type experience.
PSVR works really well considering the very low spec (when compared to competitors). I think there's a lot more wiggle room than you'd think, depending on the application.