It might not be the most constructive way of doing things, but people tend to downvote comments they disagree with. As to why they disagree: HN's audience is n

It might not be the most constructive way of doing things, but people tend to downvote comments they disagree with. As to why they disagree: HN's audience is not representative of the general citizenry. We're better informed about technical security matters (or we like to think we are, at least). I suspect that correlates with being less willing to trust security to the goodwill of third parties.