50 years of medical innovation leading to the propagation of procedures, medicines, and equipment costing upwards of tens of millions of dollars to procure and maintain.

Nobody is equipped to try to make an informed purchasing decision on if they want the $50k or $100k option to try to save their life while bleeding out of a gurney after getting hit by a car.

Oh yea, we're forgetting about the no insurance glory days of pre-WW1 medicine!

If your definition of "worked" is letting everybody die because most of modern medicine hadn't been invented yet, than sure, going back to those days would certainly drive down costs. No need for those expensive CT scan machines anymore, just rub some dirt on it.