It kinda used to be like old reddit in here. Empirical analysis, people who read the article first. These people jump into these hot-topic threads just to piss all over it with every possible dumb thing to say. Climate denial, "Just let it get worse" kinds of comments. Knee-jerk making up stuff, and coping to make it OK.
I wouldn't be surprised if it's astroturfed bots. It's not like HN does much to filter out fake and real accounts.
You also see lots of organized flagging and downvoting of climate stories.
Outside of conversations about tech there are definitely a strong subset of special people with very strong views on single issues.
Consider the flat earth topic as a parallel. If there was no flat earth idea floating around, would we ever talk about the spherical nature of the earth? The answer is no. Why would we? What would there be to talk about? The topic of the shape of the earth comes up only because the flat earth challenges what has been settled, creating something to talk about.