Let's face it, you can only buy insurance when you are young and healthy, with no pre exist condition. When you are old and sick, you are not profitable to the insurance company at a rate that is affordable to you. You can still buy insurance, but at what cost? $40K a year?
The fundamental model of insurance is not about cost saving, but averaging cost between like risk clients. You pay what is likely to care for you plus a slight profit for the insurance industry, but you are not eliminating a problem of high cost of care.
This cost averaging can be done by the government or by the insurance, or let the people die when they are too expensive or they lose their bet (by not having insurance and live in a country without public health care).
This debate has been going on for ages, and is only about how to cut the pie, rather than making the pie smaller.