This is factually untrue. Hacker News is orders of magnitude more diverse than reddit. Discussion about Trump or US politics in general, for example, tends to be fairly level-headed on HN. Need I even link you to /r/politics?
First off what he said was not factually untrue. This very article proves his point.
Fact: There was an entire thread responding positively to fake content while voting down the few people who were able to see that the content was fake. The one man with a substantive reply was literally accused of not being "civil" when he did no such thing. This is 100% toxicity laced with false etiquette.
If you want to be unbiased you can't say things like something was factually untrue if there is a fact in the main article literally proving his point.
Really whether reddit is more toxic or HN is more toxic is up for debate. It's just different types of toxicity and there's evidence going in both directions. Don't be like that fool who in the main article.... every story and statement has multiple angles.
What HN do you visit? Any time anything remotely touching politics shows up here it gets immediately flagged, removed from the front page, and the level-headed comments you speak of get downvoted into oblivion.
more diverse than reddit? it's pretty much just coders, IT guys and geeks, most of them white right wingers, libertarians. nothing wrong with that, that's why I come here, but I am aware I am going into local bubble and I know what to expect when presenting opinions unable to respect different opinions out of their echo chamber
the sheer size of reddit already makes it much more diverse, you will find subs for any niche unlike HN, I can imagine local ratio between men : females already, diverse HN, that was good one