It is definitely interesting, but I think it is super difficult to implement in a way that will actually give a better gaming experience.
The main problem, is that realistic images, tend to have very similar contrast and tone. The images in your second post shows it quite well. As for a gamer, this pose two issues, first, it is very hard to distinguish between certain objects. And second, due to similar contrast and having to concentrate more, the eyes get tired much more faster than they normally would, which would result in the player spending less time playing the game.
3D games can do this because they have a 3rd perspective that helps greatly to visualize the different objects, even if they look very similar. Of course, the use of fog, shadow and Ambiance Occlusion helps a tonne. But with 2d games, it becomes almost impossible to balance between Realism vs making the game visually easy to understand. I think that is why nowadays, many prefer mixing them. Using realistic textures, shadows and rendering, but on a non realistic color (a vibrant color almost always). If you watch most of the 3D animated movies, series and games, you will notice that many of them prefer using this. You get a sense of realism, but the vibrant colors makes it visually attractive.
......well that's just my humble view.