You've got a point, I guess. (I'm talking about the present situation, not years ago, but fine)
I'd still say there are more grown up anime then there are western cartoons, though. Besides, there are many things you can find in anime you can't find in the west. (and vice versa, i suppose) There's the giant swords, the hectolitres of blood, the facial expressions, the fanservice, the really weird ideas, etc. While the graphic style obviously differs from one anime to another, it usually has a fairly different feel to it then western stuff does.