I spent last Saturday night in my very own movie theater. It seats a hundred, but nobody else was there. Technically, I wasn’t even there: I was lying on my couch staring toward the ceiling, wearing a virtual-reality headset. I spent the night binge-watching “The Office” on an enormous screen nobody else could see.

As VR continues through the same ups and downs of any other “Is it the future?” invention, the technology itself is evolving fast: HTC recently released the new and hugely improved Vive Pro, while Microsoft and...