Scarcity can be a product of reality or a product of market conditions. One of the things that eliminates scarcity better than anything else is the profit motive. This drives more players into a market.

Now a person who thinks of systems as fundamentally static sees the high prices as a fixed given but once scarcity is gone, the prices start to shift. A more crowded market can see benefits from innovation (more value for the same price or less cost) and competition (similar values for less cost). 

The chief thing that prevents scarcity from being addressed is government licensing and regulation. I will argue, without supporting it thoroughly here, that no market monopoly has ever been maintained without a shift in regulation/licensing to prevent new competition on the part of governments.

What existed before the ACA was not a free market and what the Republicans propose isn't one either. For historical perspective see the podcast I have linked in A History of Strangled Health Care in the United States.

Argue that the Republicans are wrong all you want but they are not now and have never (during my lifetime) been for a free market in medicine (or just about anything else). They are consistently about cutting taxes, increasing government spending, and pandering to the Christians.