I think it takes a unique type of psychological sophistication and narcissism to be a true charlatan/bullshit artist. There are almost no public figures that I can say I believe are total frauds. Some people can have moments that are fraudulent, with almost every politician, but the psychological position you put yourself in when you are a total fraud takes a lot of effort.
It is much easier to buy into your own bullshit. It is less isolating. Our minds naturally buy into the narratives we tell it. You can sleep at night believing you are a positive force in the world.