> Historical breakdown doesn't mean much since very few people were computer programmers at all back then.

Programming was a different affair too. You have to be much more detail-oriented to deal with punch cards and spaghetti goto code; this means fewer people get to be big-picture focused.

Going back a couple decades further, computers were huge halls where women did small calculations by hand; someone (Oppenheimer, Feynman or some such) did the big picture work and divvyed it up much like physicists now give Matlab or Fortran work to do.