Assholes tend to think simplistically.  Not about all things, of course; when it comes to something they like or know a lot about, they will be happy to argue the nth nuance of the nth detail until the cows come home.  But about anything else, nope, it’s black and white, right and wrong, and they’re right and you’re wrong, so shut up.  They have a tendency to steer conversations into their fav-talking-points so they can amaze and astound people with their superior knowledge, but they also have a tendency to impose their opinions even into conversations where they really don’t know much about the topic at all, or perhaps they have a smidgeon or two of knowledge and so, they’re “experts”.  My mom always said that you have two ears and one mouth for a reason — assholes seem to have forgotten, or rejected, that bit of wisdom.