So what I'm suggesting you think about next time you comment is how much weight you're donating to that comment by dignifying it with a long response.

Another thing to consider is that when you take an ill-considered and mean-spirited comment and pick it apart in detail, you beg other people on the thread to critique your analysis. At which point (from several years of experience on HN) we're all off to the races in a meta-debate, the terms of which were set by a self-evidently terrible comment.

When you see terrible comments like this, just vote them down. Or, if you have to reply, vote it down and then write a careful reply, with brevity.