Study: You can tell if someone is smart and male or female by looking at their brain

A recent, amazing study looked at how strongly the morphology of the brain (as measured by structural brain MRI scans) predicts IQ and the sex of the research subject.  The graph below shows the results from two different data sets.  "Morphometricity" on the y-axis is defined as the proportion of the variation of the trait that is explained by variation in brain morphology.

The morphology of the brain explains NINETY-FIVE percent of the variation in IQ.  In other words, intelligence is very strongly predicted by the "architecture" of the brain.  And gender?  Morphology explains NINETY-THREE percent of the variation in sex, or whether the subject is male or female.

In a table not show here, brain morphology only explains 55% of ADHD, 50% of schizophrenia, 38% of autism, and 20% of Parkinson's. 

Now, if gender and IQ are merely social constructions and are not biologically meaning, why are they so closely related to brain morphology, even more closely related than several brain diseases?  People who push the biology-doesn't-really-matter-for-IQ-and-gender view are idiots and liars.