This is a path trace. Such render can take hours (and there is no temporal denoising in Uneal yet). Now, VR, must render the scene twice, once per each eye. Also, VR should run at relatively high framerates, such as 90 or 140 FPS. I think achieving this quality in VR won't be anytime soon.

That said, the scene might not be too far off when using Lumen, which is a performant global illumination method. I'd like to see the scene rendered in Lumen and shown side-by-side.