Medical Costs

A very left wing blogger writes:

Saying that voucherizing Medicare merely wouldn’t “hold down costs” is far too charitable. In fact, the evidence is unambiguous that voucherizing Medicare would increase costs all things being equal, since private insurers are clearly less efficient than actually existing Medicare.

It is worth noting that countries with public medical systems seem to get similar health outcomes at much lower costs.  I am unclear why "privatizing" of medical care is limited to shifting the costs to patients instead of a single payer.  Why does it not tackle licensing issues that result in a medical doctor shortage (which raises wages and thus costs)?  Or open up prescribing powers to more providers (why can Pharmacists not prescribe?)?

It seems to be odd to focus on this one aspect of the health care segment of the economy and not even discuss the other regulatory issues involved.