> Costs will go down to managable levels […]
Why? Because of market mechanisms? It just means that a host of rare diseases will never become affordable, because of the basic supply and demand formula. Most people don't need care most of the time. Healthcare is not a commodity product.
Insurance solves a real problem: nobody knows if they will ever need it, but statistically we know that if everyone pitches in, everyone that does need several yearly salaries of care can get it when they need it.
This is called solidarity, and it works rather well in a large part of the world. Ideally, insurance is required and well-regulated to prevent excesses and to support the poor (and it is in many countries, including many European nations).
Private care without insurance is what we had in the past, and it basically meant that the rich could afford care, while the rest just prayed they never got anything more serious than the common cold.