This seems logical and tempting, but there obviously must be some reason societies haven't evolved to do this? My suspicion is that those remaining 40% are sig

This seems logical and tempting, but there obviously must be some reason societies haven't evolved to do this? My suspicion is that those remaining 40% are significantly less employable, and you can't just swap them in like a fungible good. I suspect also that as technical skills become more valuable - and our education system remains stagnant - that 40% number will grow.