But to your counterpoint, let's say the story is 100% true, because I agree it is at least plausible. What would the incentive be for the HN audience to believe it? What priors might support their disbelief? For my part, I don't think it's because people lack imagination. I think it's quite rational to question the authenticity and impact of the claims being made. What's worse, believing the story and being wrong, or not believing the story and being wrong?
That said, I agree with you: the impact we're having by not changing course is quite dangerous, the scale is dangerous, the inability to reverse the harms is dangerous, and the lack of collective effort to regulate further damage is dangerous.
It's true, humans are dangerous when trillions are involved. See: climate change.