Just like nobody is building houses like that house that cost our grandparents $8k (insulation was crap, probably not centrally heated, no ducting, definitely less sq ft, fewer windows, etc).

Here is Cripple Creek:

The startup cost is so much higher now because we expect a clean drinking water system, sewage system, roads...and we'd still call it "roughing it" if that's all we had. Most people in the US would not be willing to live 6 months without a public water system or sewer system. This is to say nothing about how much slower it is to build because of regulations.

I suppose my answer is that we have much higher standards/expectations now and are generally not willing to live with less for very long.