Framing is a plausible place to optimize, so how about steel? The factory cuts all the pieces to be assembled on site. It goes up real fast. This is what we want, right?
The trouble is that most house plans are not put together to a sufficient level of detail for this to work - contractors rely on all kinds of field decisions/adjustments.
I'm currently in the process of having a house built, and it's infuriating to me as an engineer how little detail I'm allowed to have either before or during the process. I have to rely on change orders to fix things that were totally preventable/plannable.
Hubris in particular because I'm sure architects think a lot about this and if they don't do it it's for some good reason... or they have done it and it just doesn't effect the market like I imagine it could.
I read about a government research program into building (70s?) that failed to reach its own goals but did advance building standards, and this does feel like something where government funded research could help. Something closer to how highway safety research is done, as opposed to scientific research.
There are prescriptive codes for everything "normal", so you don't have to consult an architect or engineer for structural things on most "common" houses. Figure anything up to 2x median purchase price probably can be built without either an architect or an engineer.
It's a crazy world and I don't disagree with you, but the housing market really doesn't work like one wants to think.