That's not true, it was more of a "straw breaking the camel's back" situation, and he has in the past personally acted in inappropriate ways for many many years.
All these are just allegations. If his alleged misbehavior is as frequent as it is being famed, then it should be relatively easy to provide some evidence. The man was filmed eating stuff off his toes ffs!
https://medium.com/@selamjie/remove-richard-stallman-appendi...