I think this subconsciously comes down to the fact that people don't want to or can't believe that people with power could be as evil as they actually are.

I think this is down to a couple of things. One, people would have a kennel of responsibility if they acknowledge the evil of those in charge, and they are too comfortable to want to do something about it. And secondly I think people don't really understand how corrupting power actually is, when though they see microcosms of it in something like a Karen.