I'd say that generally speaking I have not. I've made it to a point in my career where I interact with the top management at Fortune 100 companies and I have not at all found them to be psychopathic or power-hungry. Actually generally the opposite: those traits seem to be selected against.
There are of course counter examples but I'd argue they're rare.
I'd say that you'll find the psychopaths and power-hungry individuals in the middle layer of companies with the "do nothing" bureaucrats at the bottom of the management hierarchy, often without any formal people management titles at all.
In corporate politics there is only one thing that 'wins' and that is profitability. That profitability comes from the workforce so the top leaders are usually very motivated, democratic people because the best ideas win and you need people on your side.
Thinking about the public sector, there is no KPI for a 'win'. When we try to start using statistics it becomes 'political', skewered, or hand waved away as a complex marcoeconomic force.
Scheming, lying and political maneuvering at the expense of your peers is how you become the fake-friendly "Bob" or "Mike" calling the shots at the top. Non-founders who raise through the ranks largely depend on these traits. Feelings and empathy are selected away as they lead you to be passed over in promotions.
But yes, the observation you mentioned is indeed interesting. Hence the tendency of many people to think that states would also be better if run like a corporation, the desire to elect leaders that are (or pretend to be) successful managers, and that other observation that capitalism is not synonymous with democracy (and adopting capitalism does not automatically lead to democracy, as can be seen with China).
I think that you're making that up, dictators don't really need to be oppressive to remain in power. If that was true, most dictators would be quickly replaced early in their reign because there would be so many "more oppressive" people nearby, and that would only stop after "selection" done its job and a truly difficult to replace oppressive ruler was found. But that's never the case! When a dictator raises to power, usually chosen by the elite, they tend to remain in power for several decades.
https://www.ribbonfarm.com/2009/10/07/the-gervais-principle-...