1) Extremely rude, disrespectful, or hateful.
2) Pushes conspiracy theories as truthful. Like anti-vaxxers.
One of the reasons I value HN is to read opinions that are the opposite of mine. Sometimes they bring up points that I've never considered, other times they make me think more about my own positions. At the very least I might better understand the reasons for other opinions.
I would rather read a news story on HN with the opinions than just read it on a "regular" news site, even something reputable like NYTimes. I feel I learn more about the topic.