My own belief is that most people are trying to do their best. It doesn't mean they have no nasty side, or that they don't have a bad temper, or that they have never done anything they feel ashamed of. But fiction operates on people waking up trying to be horrible, and I don't think most people are trying to be horrible.
What I dislike about movie culture is that it often presents a parable of our problems - but the issues are all straightforward and the people are either nice or they're not. In real life, everyone falls between those perimeters, but not many American films operate in that grey area.