If it impacts his effectiveness in leading the FSF, then it absolutely does matter.
If he's abrasive, then nobody will want to work with him, and by extension people won't want to work with the FSF.
We shouldn't have to play this politically-correct bullshit game of tiptoe: Richard Stallman's social skills are shit, and saying that he's not well suited to a people-facing role is not some attack on him.
>conforming to someone else's views should not be a necessity to work in your chosen field.
It sounds like you don't know the difference between bootlicking and subtlety. While the face of the FSF being unyielding on Free Software is generally good, the face of the FSF being unyielding on,say, nosefucking with plants is less so.