It DOES look rather colorless, to the point of it being unrealistic. I'm so disappointed that they dropped Xenoblade's wonderful art style for this generic, grayed-out, "realistic" art style that 80% of games nowadays use. Maybe that's a bit of an exaggeration. But a disappointing choice, to be sure. --- Mario vs. Donkey Kong is a hideously underrated game.
HD has nothing to do with the color. Stop trolling. Or at least stop being silly. The art style is why anything has bright or realistic in its gameplay. High Definition only applies to the picture on whatever is being broadcasted. If anything, video that isn't in HD naturally looks faded and blurry as opposed to video in HD. Look at HDTV; bright colors are still used and look even better.
There is a point, a different point for each genre, at which realism is no longer a good thing. And when it comes to fantasy adventure games, that point comes very early. --- Never heard a man speak like this man before.