Glasses-free front projection tech should be coming out for Avatar 2-4 and if that works out I bet 3D will see a resurgence.
It seems that most people complain about 3D for these reasons:
1) More expensive
2) Wear glasses
3) too dim
5) ghosting (low extinction ratio in polarization-preserving screens resulting in crosstalk. I find this really annoying)
5) low fps
4 is likely a combination of 3 and 5, and all those are being worked on except for 1
I don't care all that much for "fake 3D" movies, I'd rather see it in 2D. But I love 3D generally. I just think at this point VR is going to be the saviour of stereo 3D. I mean, you have Spielberg now saying VR is "it" and VR requires not only stereo, but high framerates too, so the future is coming no matter what the gnognards say. Progress is happening, count on it. And HDR exposes low framerate artifacts, making HFR more and more necessary to avoid people suddenly realizing that hey, these jumpy pans and blurry action shots don't need to look like that, nor even do. Once filmmaking goes to light-field cameras, they'll be able to sell people 24, 30, 50, 60, 120 fps versions of the same movie, in HDR, in 3D, in VR, whatever. Theaters seemed to be all about "choice" but once the choice for 2D or 3D is removed, and there being no choice but 24 fps for 99.9999% of movies, I don't see the value for my dollars compared to staying home, where I can see movies the way I want to, albeit a few months later. With a drink in my hand. Pause it. Change the volume. Use frame interpolation.
I see Cinemas being victims of their own success in a way, every empire rises and every one must fall. That truism must include commercial empires. Nothing lasts forever. 3D failing in the cinema is only a sign that 2D will also fail eventually too. A "big screen" is moot when you can get a VR helmet with perfect blacks and HDR and retina resolution with spatialized audio giving you full field of view. I could even see animated movies being republished in 360 degree 3D eventually, with HFR, HDR, full rec 2020, all the other goodies too.