This is only true is you assume that higher IQ necessarily improves reproductive volume in ancestral scenarios. There's no reason to assume that. IQ just wasn't

This is only true is you assume that higher IQ necessarily improves reproductive volume in ancestral scenarios. There's no reason to assume that. IQ just wasn't that useful until very recently in history and would have been detrimental in many ways. What is a genius going to do with all his smarts if he's born to illiterate medieval farmers or tribal hunters? It just means he'll ask questions that annoy people and get distracted by reproductively irrelevant thoughts. There's no math to do, no books to read, no machines to improve, no big complex systems to understand. IQ is not historically adaptive in the evolutionary sense. If it was, we'd all be a lot smarter. If you doubt this, just consider animals like chimps, dolphins, or elephants. They could have evolved higher intelligence, but it was more adaptive for them not to.