Social media upvoting/downvoting that results in comments being hidden is the reason for this. Even a small imbalance in one direction or the other effectively silences one side. Perfectly legitimate, well-reasoned comments will get angrily downvoted into invisibility. Echo chambers get created and enforced. This is particularly bad on Reddit (low karma can get you banned from a sub) but even on HN I'll give anecdotes that go against the "party line" and I'll get downvoted.
Problem is, this is the best way to increase engagement because it gives the most people the most compelling content. So this will never change.
I agree but i think HN does a somewhat Ok job with the upvoting system. Well at least compared to reddit which is in a full blown meltdown because their bubble popped.
Some ideas I'd like to see implemented (in no particular order):
1. Eliminate anonymity by requiring real names and profile pictures attached to usernames. This humanizes users and encourages accountability, as attaching a real name can act as a natural filter for behavior.
2. Introduce a cost for downvoting to make it a more thoughtful action. This could involve a quota based on account age and karma, or my favorite option—having each downvote cost a bit of karma or an upvote on one of your own posts.
3. Discourage bot accounts by requiring a hard-to-obtain token, like a verified phone number, which is straightforward to implement and would reduce low-effort accounts.
4. Higher barrier to entry to join an online community. This doesn't parallel how communities work IRL. You need social credit to join a community.
Problem is, this is the best way to increase engagement because it gives the most people the most compelling content. So this will never change.