I'm tired of people saying that! For a lot of fans, Ang Lee's Hulk just overcomplicated a very simple idea. No one's saying the movie wasn't supposed to have depth, but jesus christ! There was a lot of crap that didn't need to be in that film. The Jekyll/Hyde allegory was just fine without all the added stuff with Bruce's father, and all his experiments, and ultimately becoming the Absorbing Man, since god forbid a superhero movie not have a supervillain, even though Hulk is such a character that his origin movie shouldn't have even needed a supervillain.
So, we should hire lesser known actors who aren't talented?
One doesn't automatically lead to the other. Whether or not an actor nails a role has nothing to do with how well-known they are.