You are seeing the outcome of structural problems that plague any site that puts pseudo-moderation tools into its users hands. Voting and flagging has been weaponized on this site for far longer than most HN users would care to admit.
In fact, I feel like HN is much worse about promoting echo chamber behavior than Reddit, due to the visibility differences between a comment being downvoted/flagged dead, as opposed to merely being greyed out and collapsed.
If you haven't noticed it before now, it's because the incentive structure is weighed heavily in favor of the echo chamber. Those who engage in good faith eventually get tired of their comments being hidden by an unaccountable mob and leave - and to be clear, I am speaking in the past tense, as in this has already happened to HN several times over.
In fact, I feel like HN is much worse about promoting echo chamber behavior than Reddit, due to the visibility differences between a comment being downvoted/flagged dead, as opposed to merely being greyed out and collapsed.
If you haven't noticed it before now, it's because the incentive structure is weighed heavily in favor of the echo chamber. Those who engage in good faith eventually get tired of their comments being hidden by an unaccountable mob and leave - and to be clear, I am speaking in the past tense, as in this has already happened to HN several times over.