Game theory and personality dynamics strategy applies to C-levels too! For some industries, companies, etc you want to be a Holmes type of total confidence. It depends who your market is, and by that I mean the VC's you want to attract. If they go for the "arrogant boy/girl genius" schtick then that's what you do. If they want a humble intellectual, then that's what you do instead. Conversely, you may alternate between the two depending on your audience. Maybe you're humble in HN comments, but maybe a monster in VC meetings. Look at Elon's larger than life "boy genius" PR persona. It works really well. He may not be a total fraud like Holmes, but his shoddy car AI has killed at least a couple people in cases where if the car had a lidar-like system, that truck or whatever would have been identified instead of seen as part of the sky.

Also Cruise wants to license to automakers, not make their own car, so they have to act like trustworthy partners in their PR. Elon has his own car company and instead is antagonistic and belittling to automakers because he thinks there's a competitive advantage to it. Any positive sentiment towards his competitors is potentially lost sales for Tesla. Capitalism encourages zero-sum thinking and rewards zero-sum strategies.

CEOs are marketers and salespeople primarily and as such know how to play different roles for different situations. They code switch just like everyone else. The role isn't for everyone in tech because a lot of tech people don't have the people, political, and acting skills for it.

tldr; capitalism doesn't work well with honesty, in fact it works best with dishonesty. You don't have a personal relationship with a CEO or company, you're just absorbing marketing delivered via executive personalities. Personalities are perfectly valid marketing tools in capitalism. Take that as you will.