Assistant professors (tenure track) in decent public business schools start at $300k salary. And this is in the Midwest. And I know that the top private business schools pay more, just that it isn’t public information like it is at the public universities. Now obviously those people would likely be paid higher salaries in the private sector (even CoL adjusted) but the economics of it ensures that pay for professors of fields in demand in the private sector will be at least somewhat decent.