The types of persona that seems to take off in popularity often seem to involve a lot of screaming, yelling and narcissism. I think its less that everyone is the same and more the types of people who make these headlines.
YouTubers are people. Some people are assholes. Consider the thousands of YouTubers you don't hear about. I doubt the percentage of assholes in the community differs significantly from the general populace.
Basically this. There's definitely some confirmation bias if your conclusion is that everyone is an asshole.