Humans don't have some kind of overall "morality" or "judgment" setting that applies equally to all areas of life, where a failing in one area translates to failings in other areas.
You can be an amazing CEO and a terrible father. You can have the best judgment in the world around mothering, and abysmal judgment in business. Most importantly, you can be totally trustworthy in the realm of business, yet not in romance.
The idea that there is this binary switch, where someone is either perfectly trustworthy in all contexts, or else you can no longer trust them in any context, is just not an accurate understanding of how real human beings work. It's not supported by modern psychology.
At the end of the day Jensen chose to have an affair with a senior officer of a company strongly suspected of bypassing trade restrictions and should have known that it would be a terrible look for Nvidia and himself. Even if he didn't suspect her of being an agent of China, even if he didn't believe the allegations against Mega speed, even if he had no intentions of passing confidential information or aiding in bypassing trade restrictions. He knew it would carry the appearance of all those things.
That is the unforgivable lapse in judgement.
If you can't adhere to the terms of a voluntarily-entered personal contract with a person to whom you've promised utter faithfulness, why should I believe you'll be trustworthy with regard to some boring, impersonal business contracts?
My company is willing to hire my wife, but she wouldn't be allowed to work for me, nor I her.
- Signed, another European