My first house, a townhouse, was built with 2x6 exterior walls 24" OC, it also had 1" of extruded styrofoam on the outside and 5.5" of fiberglass insulation in the walls. With only the front, back and roof exposed to the outside, it was pretty cheap to heat and cool.
Builders can be slow to adopt new tech because they have been bitten in the butt by some latest and greatest: polybutylene plumbing, Masonite siding, aluminum branch wiring. Some new things are pretty much accepted now and widely used: OSB instead of plywood, roof trusses instead of rafter and joist, floor trusses and I-wood beam floor joists, prehung doors, manufactured stairs, etc. As trades training has died in this country and labor costs have gone up, products that help a builder build faster with lower skilled employees and subs are readily accepted.