If you are good at running an airline profitably, you are obviously an expert on aviation, and you provide a useful product for airline passengers and employees and stockholders.
Great.

But if you can jump from an airline to banking, or then to a chain of supermarkets, then you are good at running a business, not at aviation or finance or grocery marketing. You are good at making money, not at providing a good or service to society. To you, running a business isn't about fulfilling a need to the public, its about fulfilling your own needs; its about self-actualization based on exploiting the labor of others. People like this use their "business acumen" to keep score, its how they rate themselves against the rest of us. I realize people like this are highly prized in this society, but to me they are samurai, mercenaries, sellswords. They give me the creeps.

A business should be about serving the public, and if you are good at that you should be rewarded for it. But if a business is just a machine for generating profit, then it is a fundamentally flawed and predatory institution. Or perhaps 'parasitic' is a better term. These guys will milk a market dry, sell their company's reputation off for parts, and then move on to something else, leaving their their customers and employees holding the bag. They only care about people just like themselves. They have nothing but contempt for anyone else. I don't know anything about Cuban, but I suspect deep down inside he's just like Musk, or Trump, or Scrooge, or Capone.