Interesting data point. My father-in-law was a math prof who gave up research. He felt bad about it. He went to the department chair and said that since he wasn't doing research any more, could he be given more classes to free up other professors who were doing research to spend their time that way.

He was told no because, "It would make the rest of us look bad." And so he spent many years working a half-time job and feeling bad about it.

(He was also one of the best teachers in the department. In large part, possibly, because his attention was on teaching, not research. And face it, most of the material that is presented in first and second year math courses has not been a subject of research since the 1800s.)