Pretty sure this is the right answer and calling this "worker productivity" seems a bit harsh. A "Pretty Good House" (book that was on the front page last week) includes insulation above and below the foundation slab, vapour barriers, double studs to break thermal bridges, complex window installation (again thermal bridges), air exchangers and heat pumps with ducts (or mini-splits).
New constructions (for cold zone), need to be air tight and that certainly comes at a cost in time as it is work to apply all the layers, run the conduits and whatnot.
New constructions (for cold zone), need to be air tight and that certainly comes at a cost in time as it is work to apply all the layers, run the conduits and whatnot.