Government permitting is now a huge percentage of the cost of building a house in many US metros. CA is maybe the worst offender.
It's not just NIMBY. State and local governments have gotten exceedingly greedy over the past several years.
I’m currently building something in a much more lax area, but even here, the few parts that require permits/inspection are by far the largest hurdles, because they impose a rigid sequential order of operations that have to happen before I can move on, and require a licensed master tradesman to pull the permit, whereas most other things can generally proceed as materials/equipment/people become available.
On your point about local government getting greedy, I went to the state of the county address in our area recently, and the county executive gave a long laundry list of how many millions he was splashing out to x and y, to fanfare for each spending figure, as if the goal was to spend more, rather than get the maximal impact for the dollars. I guess most of the audience were people from those departments receiving the additional money, but as a non-government worker, it was a bit sickening.
I don't see how a contractor could be efficient at all with this setup - I'm assuming they're better at getting things through building and planning, but even if it only took them a couple weeks, they'd need a pretty big pipeline to keep busy, to compensate for all the stalls.
zoning regulations and entitlements are only one piece of the puzzle. a significant piece, for sure.