Well, once you have tenure you don't really have to do anything. And I find it hard to dislike research when it becomes "research on whatever you want". In most jobs where you have to think, you're encouraged or have to do some sort of research. It's the same with being a tenured professor, except you don't have to do the research, and you are more free to choose what kind of research you want to do, and you are more likely to be recognized for doing it, and you are more likely to actually make a difference in an important subject.
The teaching requirements are usually minimal. A lot of the work is done by teaching assistants, and the non-grading work can be a lot of fun if you care about the subject. Showing people things you find interesting, teaching them about them, and thereafter being responsible for those who further advance our knowledge, or just make some sort positive contribution, can be quite rewarding. I don't really see the drawback.