Seems like everyone skipped over this part, but optical controls for motorized wheelchairs is a cool idea (at least to me, maybe that's an old idea).
Full VR hasn't done well, but it does continue to make me wonder if there's a market for a stripped and slimmed device. I'd maybe be interested in a device that does optical controls if it fit in regular-sized glasses. I'd be super interested if it had a HUD system (even a super basic one that can only show a handful of symbols). Better still if it had some basic audio, but maintaining the "regular glasses" form factor is more important to me than the HUD or audio.
Seems like a pretty strong indicator that AR glasses are still being worked on, this definitely feels like one of those features Apple ships to refine before the proper hardware is ready.
It's been done for a while - follow the links to who they reference. ie https://www.tolt.tech but it's their integration they've done into the OS is interesting.