Fancy use case scenarios might sound amazing, but in the end, when we talk about an end consumer device for gaming, I doubt it will go anywhere. People in general are lazy. That's why anything like the Wii and Kinect didn't get any traction long term as people just want to sit down with their gamepads. Nobody really wants to be up and about playing games, they want to sit in their couches. That's the reality of video gaming.
There will be extreme niche use cases in some enterprises (eg. Microsoft Holo lens).
Apple has to come up with a new use case.
My guess, Fitness+. Fitness instruction over a 2D video sometimes is not that intuitive as you can only see one perspective. Putting this into VR/AR might be an interesting application, as long as Apple can keep the weight low and comfortable to be worn in a lengthy period. Maybe that's why they are aiming at that lower weight target for the device.
Sure, people may find that they don't want to use VR controls to play games.
My point is that I don't think you can use the lack of traction of the Wii and Kinect style controls to predict the success of VR controls.
The Wiimote was quite basic. All it had was an accelerometer and a camera that could see 2 LED targets on the "sensor bar". The position and movement of the controllers in 3D space was only a rough estimate. That meant that it could mostly only be used for imprecise movements in casual games, or to make gestures in place of a button press. VR controllers are much more capable. But even if the Wii controllers had been as good as VR controllers, it wouldn't have helped much because using a 3D controller to control movement on a traditional screen is unintuitive, as I explained in my previous post. There's a similar issue with Kinect technology.
Wiimote-style tech has ended up in other game pads. Playstation, Steam, and Switch controllers all have better motion sensing tech than the Wiimotes. My TV has some Wii-style pointer functionality it its remote.
There are VR games and apps that work while sitting down. There's a game called Moss that lets you controller the main character, a mouse, with traditional gamepad controls, to move her around a 3D diorama. You can also occasionally grab and move certain things in the environment by physically reaching out you hands/controllers. Sony has a similar game with Astro Bot. Also, just playing multiplayer card games is more fun in VR. Probably the biggest issue with sit-down VR games is that you can't have as much camera movement as in a traditional game without causing nausea.
Maybe some VR games would work best on a floating 2D screen, but you can also have an inventory of 3d items around you that you can quickly grab instead of having go into a menu.
I think fitness will be one of the early use cases that Apple pushes.