There are a lot of really dumb CEOs
See kliavkoff.
It's not like there's a national test for the best decision makers. If they did that, you'd have an argument. Instead most get into these positions because of who they know, who their parents were, how effective the people around them at the last job were, a lot of luck, and some skill.
But don't oversell the skill. It's not worth the billions they're paid