Thats because red is not usually dominant color in nature. Blue is sky and seas. Green is well rest of earth for most time we as humans evolved. So normally our eyes perceive those colors as more natural. This however is just a rule to get to photo-realistic image easier. Its does not mean that reddish images cannot be extremely photorealistic .
To me, it does not matter much. One should strive to improve himself, render engines are fine :D
Totally agree with you. A to of 3D realism is about creating lighting, colors & contrasts we are used to in real life.
However, as you mentioned, reddish light is instinctively perceived as more "artificial" and "unnatural"... probably because from those hours of daylight,
only a short period is dominated by red light.
Also, if you look at small rooms with weak, reddish lamps in reality... it is really unpleasant to the eyes... and it looks exactly like what it is: artificial... no matter if in a render or in reality. :)
Regarding "render engines are just fine" and it is up to us to create realistic images, I only agree 50%.
If the render engine simply does not simulate stuff, you can be Leonardo DaVinci and your images will never look real.
Just remember render engines 10 years ago... :))))
However, Corona is without doubt one of the best render engines on the market. I think among the top three.
And it is developing quite nicely.