Isn’t that also HN? I don’t think the existence of the down button is a factor as much as the moderation. FB is a nightmare without a downvote, SO is like a dysfunctional family, and HN seems to mostly work.
In a way it is. But I think it works much better for comments/discussion as on HN, than getting downvotes for your cat picture or SO questions. Perhaps it's because even though HN downvotes should be on quality not content - that's not what the majority of downvotes are, they are disagreement. And people accept disagreement.
