As far as I can tell, the discussion was on-topic given that a former professor, Minsky, was being accused of "assault." Stallman's questions and statements revolved around the use of that term and the trouble that its lack of specificity brings.
The university is (ideally) full of scholars holding controversial views, asking uncomfortable questions, and being accused of all manner of crimes. If one of them (Minsky) can be tarred and feathered without a trial, any of them could be.