Being vulnerable to espionage seems like one pretty obvious way.

If he is willing to betray his wife, who else is he willing to fuck over?

Yes. Unreliable by having an affair.

Not because he had an affair (who cares, really, and hardly uncommon), but because he had an affair that endangered the company, and in some respects our country.

Functionally, it's not different from "left an unlocked phone at a bar". A mistake anyone could make, but, when you're paid what he's paid, that type of mistake is the thing you're paid not to make.

Because these are known risks for a CEO of a top 3 market cap company. Not to mention there is still to be an investigation on if it was on purpose.

This a known attack vectors that global security teams and front of house security teams go over yearly with C suite.

It means that you’re dishonest and can’t be trusted to keep big commitments. That seems to be less valued than it once was though.

If he's lying to his wife who else is he lying to?