He actually doesn't reject the premise. He throws around a lot of chaff about other characteristics on which to distinguish people, without addressing the issue

He actually doesn't reject the premise. He throws around a lot of chaff about other characteristics on which to distinguish people, without addressing the issue that the groups he's ridiculing postmodernists and marxists for being concerned about actually do suffer structural inequality, then ends by saying that he's not obliged to care about the historical circumstances which have favored him in the development of that inequality.