>Because we have no moral or social pressure to not delegate everything?

"We" depends on where you are. Countries like Japan or Germany have maintained a gray collar, rather than a blue/white collar culture for exactly that reason. You will find business owners on the workshop floors frequently because there is an understanding that divorcing management from tacit work is going destroy leadership ability. That's the basis of vocational work culture, having general expertise across all domains of your job rather than being a kind of over-specialized idiot.