Of course, the spy aspect could be relevant from a professional perspective (depending on what actions he took or what he knew), but I'm guessing you're talking about him having an affair.
In fact, the affair was less important. Even if they were just a very close but unromantic professional relationship it would be a serious scandal.
Most posters in HN don't think "poor corporations are the victims when they are hacked". They think "the corporations should be liable because they did not invest enough in security". This is morally the same.
Yes, in many places, absolutely. Bad decisions in your personal live suggest bad decisions in your professional life.
It is not so clear, if this is about his character and can he be trusted. This is evidence that someone is capable for lying and doing something that might not be in line with company ethics either. I don't think we can assume from humans that "he lies only in his private life, but can be totally trusted on business side".
Nowadays, we make them president.