>>16674907
>Do people really think that biological variance just stops
No, but tangible brain things show factually stronger correlation with developmental factors, unless the brains in question are genetically straight up broken (massive developmental disorders). Hence the utility of IQ - it's only good for formally filtering out legit brain damaged cases en masse, like in military draft.

Essentially software matters much more than hardware for all cerebral shit. A good program runs pretty much the same on next-gen and last-gen biological CPUs, and even the best CPU evar can't contribute shit if runs on garbage software. That's why historically greater involvement of intelligence in a society always required wider and better education, not incestuous breeding programs. If it was the opposite, Hapsburgs and ither inbreds would dunk on everyone. Instead they got teabagged by soil tillers figuring out how to build and reload muskets.