I like Dang's comments on the idea that the presentation of the information is just as valuable as the information itself. Much like your round Earth example, sometimes stating the objective truth isn't enough to win over an audience. This isn't a flaw in HN so much as it is a flaw in the way people behave. We all operate with partial information and when new information conflicts with what we know (or sometimes what the collective authority seems to know) we reject it.
In general there are two options to this. You can fully commit to your views, and get 10 responses where opponents fully commit to theirs. Or, you can consider the general views of the community your in, and adjust your comments to challenge and question without provoking, usually getting a small number of considered replies in return. The latter tends to be the harder of the two and the less noticable. I think this is why larger discussions with more approachable topics seem to turn toxic faster.
In general there are two options to this. You can fully commit to your views, and get 10 responses where opponents fully commit to theirs. Or, you can consider the general views of the community your in, and adjust your comments to challenge and question without provoking, usually getting a small number of considered replies in return. The latter tends to be the harder of the two and the less noticable. I think this is why larger discussions with more approachable topics seem to turn toxic faster.