IQ Denialism is an extremely respectable form of anti-science conspiracy theory-mongering.
Of course, if IQ were just a delusion of white male privileged racists, it would be hard to explain how test scores could be forecast from brain scans. Slowly, however, that’s becoming more feasible to accomplish.
Steve Hsu has a post, “IQ prediction from structural MRI,” about a new paper at PLOS called “MRI-Based Intelligence Quotient (IQ) Estimation with Sparse Learning” that claims quite high correlations between data from brain scans and IQ.
Meanwhile, Emil Kirkegaard has posted on his formidable Clear Language, Clear Mind blog a draft of his paper on “The general brain factor, working memory, parental income and education, and racial admixture.”