I sincerely hope that you are using IQ as only the crudest shorthand for "ability to actually use true beliefs," but your point in general is very well taken. Please do jump in if you have a listing of the most harmful delusions. :-)
IQ >= 120 is a fairly low bar. IQ is also a strong indicator for the potential for someone's behavior to be influenced by delusions (rather than near mode thinking + social pressure being the dominant adaptation.)
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