It's just like the move from black & white to colour, from mono to stereo to surround, etc.
No no no, colour and stereo were passive improvements, the audience didn't have to do anything extra to experience those. S3D is an active improvement, as in you have to actively do something (wear glasses) to experience it otherwise you can't. I really wish people would stop making this comparison, because it's simply not the same.
Fact: S3D makes everything a few stops darker
Fact: You can't focus properly on any area of the screen that hasn't been made the focal point. Meaning that you can't marvel at some bit of the background scenery without your brain starting to get confused or even inducing a slight headache.
My theory on the current push for 3D is so that the studios can force the theaters to finally go digital, thus eliminating the need to make costly film prints. At up to $2000 each, if a movie wants to appear on 4000 screens simultaneously, that's a large amount of money the studios need to outlay. But in digital, they just ship around a bunch of reusable hard drives for a fraction of the cost. Once everything is mostly digital, S3D will die down again, like it did 30 years ago in the 80's, and 30 years before that in the 50's. History repeats.
Give me the crisp, bright normal "2D" movie please, so that I can enjoy looking at any part of the screen I want, and so that I can turn my head and still be able to watch it properly.
btw, I work in VFX and am currently working on a stereo converted movie.