If some employee of the company does something illegal, the CEO doesn't go to jail. The CEO is only responsible if one can prove that the CEO did something illegal. And that's the very least we can expect: CEOs are humans who should not be above the laws.

But you completely forget the whole spectrum of legal (including "shady") things: an incompetent CEO doesn't risk anything. They can sink a company, get fired and leave with a bonus bigger than most of the good employees will never earn in their lifetime. And then they will get hired as CEO of another company, because nobody seems to care. This is not responsibility.