I would place the shift around the discovery of atomic physics in the late 19th/20th century as when this system rewarding the mediocre people the most came about. WW2 was the last great border conflict war where lower warrior thinking and higher strategic thinking mattered. Old world statesmen for example would've surrounded themselves with the brightest people possible and would speak and write carefully. Modern politicians and people in institutes just take freud theories and send their quick sound bite messages through electronic communications. Being a mediocre thinker is most effective now because you don't overthink things but can speak with better clarity then lower IQ people then you.
