Another perspective: I read the forbidden idea, understood it, but I have no sense of danger because (like the majority of humans) I don't really live my life in a way that's consistent with all the implications of my conscious rational beliefs. Even though it sounded like a convincing chain of reasoning to me, I find it difficult to have a personal emotional reaction or change my lifestyle based on what seem to be extremely abstract threats.

I think only people who are very committed rationalists would find that there are topics like this which could be mental health risks. Of course, that may include much of the LW population.