Individually, maybe. Let alone the ethical implication of 'tax them high enough so they don't retire early', artificially lowering the income of a trade would -

Individually, maybe. Let alone the ethical implication of 'tax them high enough so they don't retire early', artificially lowering the income of a trade would - to your point - constrict *supply of labor. And of course this would lower the total productivity of the industry and society. And the Ford example, while interesting, doesn't have to do with taxes does it? It has to do with Ford lowering the barrier of entry for factory workers AND increasing productivity rate at the same time. I think we can all agree that that advancement was good for society as a whole? Am I understanding you correctly? Or is there something I am missing?