Slim, lightweight form factors similar to that of the Bigscreen Beyond are not going to be practical in a self-contained headset for quite some time to come, at least if the goal is to play anything more demanding than Terraria on it and its price range is anywhere remotely within reach of the general consumer.

The only reason why Facebook has been able to swing such low prices is with steep subsidization, and the Quest hardware itself isn't much less bulky.