Of course, but the distinction isn’t useful in this context. Proxies for intelligence, like large heads, became maladaptive, so intelligence itself declined along with cranial size. It remains valid for the original argument—that the assertion that for some groups, large craniums (or other traits that augment intelligence) may have become a liability, isn’t controversial.
and the obvious horror scenario
I guessed you had linked to Idiocracy.
That’s not exactly about intelligence being maladaptive, though.
Of course, but the distinction isn’t useful in this context. Proxies for intelligence, like large heads, became maladaptive, so intelligence itself declined along with cranial size. It remains valid for the original argument—that the assertion that for some groups, large craniums (or other traits that augment intelligence) may have become a liability, isn’t controversial.