I don't know the author, so I can't say how it's going there. I just know that one time, I did a public performance. Our team (and I, specifically) received a LOT of really awful, hateful, vitriolic feedback. It was actually regarding a similar issue . . . and I was just in shock. I couldn't even THINK straight about feedback for a couple of weeks, because I was so surprised by the force of the anger. It was hurtful.
It didn't exactly put me in the right frame of mind for responding to other feedback - even positive feedback - right away.
And as @FairyGodfeather and @Lotus have both mentioned, Sergi has responded to feedback before.
And perhaps most importantly, I think perhaps discussing the author and his practices is less the point of this thread (or any thread on the CoG forum) than discussing the story itself.
Edit: To clarify, I don't find that people on the forum are being vitriolic - we're well-moderated, as @FairyGodfeather pointed out, and most people are very thoughtful and considerate here even without the assistance of flags. My sincere apologies if my post came off that way.
My point was that we have no way of knowing what other, much harsher criticisms and even hate-speech may have come to his ears by other means.