Earlier quoted context omitted.
Whenever a topic about something that could potentially destroy humanity comes up (say, climate issues), there is always some comment that makes a reasonable argument of why things are not as bad as they seem. This never happens when prions are the topic.
The simplest counterpoint to prion cataclysm fear is that it hasn't happened yet. That implies a low chance that it'll happen anytime in the near future. There's no evidence that any significant human population has ever been wiped out by prions at any point in the history of the species. Heck, we haven't even observed widespread (>10% infected) prion disease in any species. At least with something like climate chang…
While the kinds of people who would fly planes into buildings, release nerve toxins in subway stations or club entire villages of outsiders to death have always existed the ability to research and manufacture prions did not exist in 2000BC.
That combination of desire to destroy the world and the legitimate ability to do it with rapidly more accessible biotechnology is a disconcerting reality that we need to account for when discussing theses things.
Imagine a religious extremists organization mass producing prions and placing them in key parts of food supply chain. We probably wouldn't have a clue until it was too late.