I think this is a bit of an oversimplification. Most people have a perception bias for "bad" people, but it's justified because the potential outcomes of being a victim of a bad person are astronomical. So it doesn't matter if the vast majority of people are "good", because a single encounter with a bad person can be catastrophic, so it makes logical sense to be wary if you know there are any amount of bad people around.
Now of course this instinct gets manipulated by the media and politicians and all that, but the initial instinct is perfectly reasonable, imo.