I think the lack of vertical integration could be a part of it. For example the framers don't have much incentive to make things easier for the plumbers or electricians.

There was a recent HN post on a shortage of electricians that got me to thinking why studs, which already come pre-cut to exactly 92 5/8", don't also come pre-drilled for wiring at outlet and switch height (at least I've never seen that in wood studs).