Please note that where they say 'grounded conductors,' we usually say 'neutral.' We're talking about the white wire here, not the green.
I see merit to the idea of having a neutral pass through the switch box. At least when a 'raceway' is used (conduit), you can later add a neutral if you need one.
I can see where NEMA is coming from; the various 'energy' codes are getting ever more intrusive, and their main focus seems to be lighting controls. Try adding a timer without there being a neutral present some time ...
At some point you have to recognize that there can never be 'enough code' to make things perfect. Add to that the changing nature of the world, and you get things like mixing plastic boxes with metal studs - something that neither manufacturer ever imagined.
Also forgotten are the assurances of the cable makers, their stipulation that they KNEW their product was very limited, and was thus intended only for very simple, conventional, mass-market uses - things like wiring Archie Bunkers' bungalow. Those products were never intended to be used where there were complex circuit and control arrangements.
Jobs come and go, but 'cheap' is forever. I think the code approach ia a mistake; only when the customer learns to appreciate the value of good design will some of these problems be solved. Until that happens, all these rules will do is drive more work 'underground,' to the unlicensed, unqualified, and unscrupulous "contractors."
