Actually, your response is the only weak and lazy part. I've asked a lot of people about this movie, and while I don't claim omniscience, it certainly seems if people go into the movie expecting a slasher horror movie and they don't see past that, they are ultimately disappointed. It's almost as though they don't make any relation between the teen revelers and the controllers in the complex.
But the movie is far more complex than that, and if they don't get that, then the movie is going to disappoint them.
Of course, for many, if they don't 'get' the movie, then it's the movie's fault entirely. But a lot of people don't expect such a layered story so its subtleties goes over their heads.