Why are these smart people making all of these mistakes?

I wonder if it is because the mistakes are so extreme that the original failures that lead to them can't just be ones of poor problem-solving. If an IQ test asks what can be logically inferred from some evidence, I'd expect smarter people to do better. If an IQ test asks whether astrology can be logically inferred from no evidence, I expect very low levels of intelligence to be required to figure this one out. So to the extent that people answer 'yes', it is for some non-intellectual reason which are more or less uncorrelated with intelligence.