I think you're overestimating how influential Hacker News is on the discourse of society at large.

Many people here were (and still are) solidly anti-vaccine but in the grand scheme Hacker News was just one of innumerable maelstroms on the internet, and far from the biggest. More realistically, Hacker news is just full of people who aren't any more immune to propaganda than anyone else.

I'm not blaming HN specifically or especially, I'm saying that tut tutting about all those dumb "voters" and "Lysenkoists" is shortsighted. The problem is right here. If you want to know why "they" were so dumb you only need to answer why WE were equally dumb.

My general sense is that the tut-tut set is very much an overlap in the Venn diagram with the libertarians who deliberately enabled this nonsense originally and refuse to treat with their own complicity.

But I've spent most of my limited budget on posting about this, so I'll stop now.