Especially on Show HN posts, there are people that can be categorized as fanboys and haters. Both groups add nothing substantial to the discussion. The constructive, interesting and insightful comments come from the normal users.
No, but I'm rather familiar with it. In any case, I don't see how that's relevant; the context of the discussion is HN guidelines, not guidelines for San Francisco.
We could, but I don't see any evidence that there is an amount of that going around that requires an addition to the guidelines.