Looking Glass displays (not the "hololuminescent" ones) solve many of the same things (multiple viewers, no glasses) while looking good, and in principle you could build a cube out of them, although the display can't be seen from the full 180 degrees.
I mean, I think it's SUPER cool and would not mind one sitting on my desk.
But from a product standpoint...? It doesn't scale well in size, resolution or refresh rate.
VR is pretty much better if you want a the kind of immersion I think you'd be looking for, and even selling that is hard.