I do have experience, real-world experience, with people like The Short Fingered Vulgarian. Yes, he does represent a "type."
Classic bull-shitter. I came across many of these kinds of people in my business-world experience. Corporate executives. Salesmen. Full of confidence. Big personalities. Strong-willed, goal-oriented. Deal-makers. Rain-makers.
Their lack of knowledge was not a problem. Personality characteristics: vim & vigor, brash, bold, brazen. Full of it. And never wrong. Can not be shamed or embarrassed. No backing down. Always going for the win, or the close.
Lots of hot-air. Huge egos. Their audacity was always impressive. Their lack of conscience, or any sense of humility a powerful tool. Often, essentially, they would believe their own bullshit. Totally. And that was a great asset.
Like they say, you "can't bullshit a bullshitter." The bullshitter basically thinks everything is bullshit. The world, and all the things and people in it, are reduced to just varieties of bullshit. A good bull-shitter, the consummate-pro bullshitter, thrives in the land of bullshit.