(I live in a house built from cinder blocks filled with concrete and rebar, like a commercial building. It was built by a commercial builder as his own house. It looks industrial from the outside, and nice inside. I'm fine with that, but most people are not.)

The problem is that the costs of labor and materials from the past are behind us, and there are potentially no material cost and productivity improvements to be had. The costs are the costs and potentially unavoidable.