If I was a betting man, and I am, I would bet odds are 70/30 in favor of a successful VR industry, even if it takes time to ramp up.
It depends what we consider a success. If the PS4 lead over XB1 increases because of PSVR, it's a success for Sony. But as a consumer, what I care about is sustained support, and I want the product to be still alive beyond the through of disillusionment. Neither kinect, nor move, nor wiimote managed it. The move sold 15 million, but it had little support by third parties, and almost no support beyond the first two year. It was similar for wiimote and kinect.
If we get continuously new titles (and apps) for the remaining of the PS4 generation, that's a success for VR. If we don't, it doesn't matter how many they sold. The most encouraging aspect is the third party support before launch. 90 games already announced and counting, and 200 studios developing games for PSVR. This is 10 times more than any motion gaming attempts. One of the reason is that more than half those games are multi-platform.
The important metric, for third party support, is not the number of PSVR devices sold but the number of all VR headset that can get reasonable ports. So right now it's the sum of Oculus, Vive, and PSVR. And oculus fucked it up with a kutaragi style launch. I'm really hoping HTC will be reasonably priced.