VR has much more stringent latency requirements than normal gaming, because moving your head needs to be in perfect sync with the world “staying still”. The manual calibration needed for this is around 8ms, which is compensating for the render/presentation time of a single frame at 120fps.
It sounds like a nitpick, but I can tell you from experience that it makes a very significant difference.
Yeah, well, I’m surprised it was that high.