I think the term blind spot is accurate, unless (and I doubt it) Eliezer was lying when he later said fluffy was wrong. What fits the bill isn’t a correct scary idea, but merely a scary idea that fits into what the reader already thinks.
Maybe fluffy is a correct scary idea, and your allocation of blind spots (or discouraging of the use of the term) is correct, but secondhand evidence points towards fluffy being incorrect but scary to some people.
I think the term blind spot is accurate, unless (and I doubt it) Eliezer was lying when he later said fluffy was wrong. What fits the bill isn’t a correct scary idea, but merely a scary idea that fits into what the reader already thinks.
Maybe fluffy is a correct scary idea, and your allocation of blind spots (or discouraging of the use of the term) is correct, but secondhand evidence points towards fluffy being incorrect but scary to some people.