One thing that isn't mentioned is that realism doesn't seem "cinematic." It's just like people not liking high frame rate because of the "soap opera effect," or even some people's preference for black and white. Visible grain, non-subtle bokeh effects and lens flare, etc are other things that aren't realistic per se, but for some reason they make it seem less "cheap" and bring more emotional weight than a more perfectly realistic image.

I think these sorts of forced palettes do the same thing. Maybe a different color combination will become trendy at some point, but for now, orange/blue is a pretty safe bet that it will achieve the emotional effect, without it just looking weird.