> Surrendering your phone to your VR device is a hassle.

Yes, but it is cheaper than duplicating the hardware of a flagship phone in a VR device, which is basically the atlernative, given that the phone-based VR devices are using the sensors, display, and basic compute functionality (CPU/GPU/RAM, etc.) of the phone.

Eventually, the necessary hardware for acceptable VR will be cheap enough that its not worth the hassle of surrendering a phone for it, and it will be viable for the mass market as a standalone device, but right now I think -- outside of very narrow niches -- the phone-as-core VR display design makes a lot of sense.

This is the right answer. Putting your phone into a visor is an awkward stop-gap but ultimately it needs to be something that can interface with your phone, wirelessly, so you can simply pop it on whenever you want to play around with some VR.