I get your point but I'm not entirely sure human capabilities are fixed. In fact I would opt to say that we're the only species that has evidence of not being fixed in capabilities. I have no doubt that pg was a better programmer in the 90s than I am today. However if me now and him then were pitted against each other to build some web app I'm thinking I have pretty good odds. Human capabilities are their inate skills * education * available tooling. Education and tooling improve as time goes forward (generally and hopefully).