Why? I'm playing a bit devil's advocate here, but why? Because society think it's bad and a leader should be associated with positive views? Because if they got caught they are not smart enough to be the leader?
Why just this specific thing is to be considered? Why, for example, all the Musk's "extravagances" are not ground for a CEO termination? I'm pretty sure many other CEOs have many of those "extravagances" and manage to keep their position but yet, if you have an affair, you're 100% toasted.
Maybe I don't understand enough the US culture.
This has less to do with the relative social morality of his behavior, and rather that he has more control over the boards of his companies, and his personality represents a larger percentage of the perceived values of his companies.
Meaning that the desire and leverage for shareholders or the board to actually punish him is significantly less. Shareholders would potentially be evaporating trillions in speculative market value that is not backed up by Tesla or SpaceX's actual business fundamentals.
And any shareholders who disagree with his behavior have had plenty of time to leave and take their earnings by now, which means that the remaining shareholders are a self-selecting set who is okay with his behavior as long as it keeps making them money.
In this case, Huang hit all three. Changing CEOs is also a good way to get the media coverage over faster, or at least change the narrative in the pubic (and investors) minds.
If it were just an affair, I doubt he would have lost his job. It wasn't, though, and the other circumstances- potentially dodging export controls and abusing a role of power over a subordinate- came with far too much heat, so to speak.
Also, affairs make for much more entertaining gossip than the other items, so it's probably natural that that aspect gets talked about more.
But anyway a person's character is not cleanly separable between personal and professional life, so yeah affairs add (many) points to the "not to be trusted" column.
> Business is always about trust, and someone who isn't deserving of their own spouse's trust certainly isn't deserving of anyone else's.
It is a conflict of interest same as any other. If there is no conflict of interest then the company won't care. As the CEO of the company every other employee works for him and in turn he has power over them.
Society will not like you (in the US), but nothing more will happen.
*Everything on a spectrum.