[JCharante]

I'm pretty sure that in the U.S. professors are paid way lower than what they could get in industry. They probably get at least six figures but so does anyone in the industry, especially with as much experience as a professor would.

[downerending]

Depends on the field and on the individual. In many fields, the professors would be all but unemployable. And even in hot fields like CS, some professors would not be very useful. It's hard to remember now, but back in the 80s, a PhD in CS was almost a strike on your resume rather than a plus.