It doesn't seem like it has much practical uses except for weather effects really.
Honestly VR is the endgame for gimmicks. All gimmicks are made around immersion and VR is the ultimate form of that. I don't see how anything can surpass the immersion that comes from having all your vision being the game and being able to look around and with motion controllers be able to have movement too.
Why would I want to pay more for a gimmicky impractical projector when I can buy a probably cheaper VR headset that will figuratively put me right into the game world and let me look around and even turn around to see behind me in 360 degrees.
Pretty much this.
VR to me has always been the endgame for computers being used to simulate anything (game or whatnot). For me the idea of being able to be in a virtual world that really was virtual, that was the goal for games and simulations (but, I'm coming from the POV that the uses I enjoy most for a computer are simulating things, whether it be flying a plane, being in a fantasy world, surviving a post apocalypse world, etc).
This would get you closer, but not as close as VR would. The only closer thing than VR is actually hooking up the computer to your brain and causing your brain to actually believe it is in that world.