My daughter who has autism constantly says things that could be considered offensive because she's not aware of sensitivities around race, gender, orientation, etc. It certainly can explain it for certain individuals. You can't say many neuro-atypical people don't say bad things so it can't be an excuse for him. "Neuro-atypical" is a huge, huge group of people who are very different.
The ultimate thing is though that as the leader of the FSF foundation his actions have broader consequences and demand a stricter scrutiny. He was given a loooong time to learn and improve, people have been talking about how he's actually kind of sexist and problematic for years.
Stallman's job as head of FSF wasn't just to be technically competent, which he has in spades, but to forward the mission of the foundation and a certain level of social acuity is a necessary part of that.
