That’s why it’s a thought experiment 
Here is how it’s going to play out on the mass market:
- People get headsets, great (mass adoption)
- These people use gamepads (or suitable device) and voice input to interface with the environment
- The “reach out and touch something” becomes wanted… however, you can’t just have “hand sensors” (lump term here), people go back to using the gamepad since they still need to perform actions (like… walking)
- Something akin to the STEM becomes cheap enough and wildly adopted, people can use their “hands” and still have control
- We play like this for several years while the medical field starts making breakthroughs in neural interfaces
- Culturally speaking, we start using tech for everything (the internet of things)
- Someone comes out with a consumer level neural interface
- Humanity goes extinct.
Now, this timeline isn’t necessarily a linear timeline, as several things are happening at once. Sure, you can have huge VR setups, however, I’m not entirely sure we will see those being mass adopted. Perhaps in “man-caves” / VR Arcades / Exhibitions / etc… but for the everyday person? Not so much. It’s not even about the price, but the room you need. At the smallest size, you need at least a 12ft x 12ft space or a 12ft diameter circle (this should be a bit bigger than the average distance between the feet while running - center of the pad + 6ft distance). Even the Omni isn’t truly big enough. At the most, you can slowly jog in place… full out run/sprint? Forget it.
Does this disregard anything about alternative inputs? Na, by all means, support alternative stuff! However, just keep in mind “the lowest denominator”, unless, of course, you’re making an experimental title not suitable for mass purchase / consumers.