" A comment like The author is a self-important dilettante.
is really nothing more than a pretentious version of "u r a fag."
Well, such a comment is only " a pretension version " if it is not true... and in fact becomes trenchant if, in fact, the respondent IS a self-important dilettante. Which would have bearing on whether or not to engage the person at all... I would not disagree with a person because I thought them a faq, mainly because I don't think a faq is either a bad thing or a thing relevant to many issues I would normally discuss. I would most likely not engage with someone if I thought they were a self-important dilettante, because I DO think that both self-importance and dilettantism is bad. Or, at least, I would say to them, "I think you are a self-important dilettante and I don't have hopes that the conversation will be either enlightening or productive. If we are to engage, you have to rise above your self importance."
Of course, the accusation of dilettantism might be as baseless and rude as that of 'u r a faq' and likewise deserving of scorn. But not always and dismissing it with equal scorn in every instance may be a way of avoiding scrutinizing your own sense of importance and the meaning of dilettantism.
Graham also elides a whole cateqory of 'disagreement' with the implicit assumption that everybody has something worthwhile to say and is therefor deserving of being engaged. "u r a fag" is neither agreement nor disagreement, but simple bad manners. "You are a self-important dilettante" might be a necessary thing to say, especially if the dilettante in question may be in possession of a good brain and otherwise discerning intellect (say on matters not bearing on his/her self-importance...) Intellectual endeavor is approached at with different skill sets, attitudes and skin thickness...