Well, in my opinion, the colours aren't unrealistic at all !
I was playing Star Wars Battlefront I. Makes fun.
I bought Star Wars Battlefront II.
WTF?????? WHERE ARE THE COLOURS ?????
The colours in Star Wars Battlefront II are what I call unrealistic. Because there's no colours there at all. Only dark, grey mud.
I once read an article called "the future in gaming is brown !" The title related to a similar experience the author had made that in a lot of games he had played the colours were reduced to a brownish-greyish mish-mash. No colours there at all, but instead some kind of ... well, mud.
To me, it is a fashion currently going on in gaming to take all colours away. Dark Fantasy and gothic having arrived in the mainstream. The darker, the better. Because dark = mature, I guess.
To me, that's just nonsense. A game doesn't get much better if one takes all of the colours awayy ! The gameplay is the important factor ! Not the colours !