Asimov and his fight for Associate Professor

Asimov details his battle with the administration of Boston University in the first few chapters of the second volume of his autobiography. He begins it in th is way.

On July 1, 1954, my salary was still six thousand dollars per year, but it was entirely out of the school budget now and there was no obligation to teach student nurses. This was what I wanted and I was, for the time, satisfied.

My next ambition, though, was to be promoted to associate professor. It was only at the associate professor level, according to a book of university regulations that someone had given me, that tenure was obtained. With tenure, one could only be fired for cause, and cause was not easy to get. With associate professorship, therefore, I would finally have job security.

It might seem strange that I should want job security or attach any importance to it when I already made considerably more money through my writing than at my job, but it made sense. I could write with greater ease and peace if my rear were secure; if I didn't have to spend time and nervous energy justifying my actions, if I could fulfill my teaching duties and spend all the rest of my time (some 80 percent of the whole) doing exactly as I pleased, protected by tenure.

One wonders if that is the case with most university professors these days who have tenure, they work 20% of the time, and do their own thing the remaining 80% of the time, and still get paid a humongous salary as if they were working 100% of the time? Or is it only politicians that get that sweet deal these days?