The price and inherent limitations (such as motion sickness) of VR are going to ensure that it doesn't hit mainstream, at least for the time being
(The price of the Index definitely doesn't make it mainstream though. Just trying to get a sense of this issue)
On the other hand, any game where your movement in the game world doesn't match the real world is a quick path to sickness. Any racing or flying game makes me ill, and I've been playing VR for over 2 years.
On modern hardware, motion sickness is only really an issue in VR games which move your head around in-game in ways which don't match how you're moving in real life. Teleport and physical movement don't cause issues for most people.