I feel there are a lot of compelling UI opportunities for non-gaming uses without headsets, eye tracking, holographic hardware, etc. Back when VRML was a thing, navigating a 3d space with a mouse was painful. However, with just the graphics rendering, touch displays and gestures that have commodity availability now I feel like we can break out of the icons/desktop/menus paradigm to interface with applications and data. In fact, I question whether anything of great utility can come of the fancy new AR, holograms, etc if we can't even think outside the old 2D box to interface with applications and data with the graphics rendering, touch displays and gestures widely and cheaply that are ubiquitously available right now.
The dismissal of 3d as interface for applications and data is emblematic of the absence of creativity cited in my original comment. Yes, we're accustomed to navigating folder hierarchies and invoking discrete functionality but outside of that paradigm data can be organized and retrieved more effectively. IOW, when presented with steam and internal combustion capabilities all you still want is a faster horse it's a lapse of the imagination.