There’s a really great presentation from Alan Kay from ~5 years ago where he makes a great point that VR/AR allows GUIs that we can barely dream of in the age of monitors.
And in the same way we needed to have screens and electronics powerful, efficient and compact enough to get first PCs and then smartphones, VR/AR needed progress in display and GPU tech to match retina resolution and zero out the rendering lag.
If Apple is going for it, we might be just close enough.