"I am against religion because it teaches us to be satisfied with not understanding the world."
Though it may lack the poetry & pith, maybe he should have said; I'm against religion, because it teaches us to be satisfied with an outdated understanding of the world.
In general, I don't think people are satisfied with not understanding. I doubt that the believers Dawkins was addressing think they don't understand the world and that's just fine with them.
Religion tried to address this lack of understanding long ago by attempting to explain the why's & how's while giving comfort to people living in an abstract & downright frightening world. If the rainfall could be controlled, crops would grow and people could eat. What controlled the rain? Well, it must have been some hidden agent. Hmm, perhaps we should try to get on its good side...
It was the beginning of the human quest to explain, and thus understand, our surroundings. The problem is that as humankind developed better and better ways to go about this, some of their previously treasured explanations no longer held up. And this is the problem everyone looking for answers must deal with. If you want to understand the world for what it is, you must be willing to modify, if not entirely discard old beliefs as better evidence arrives.