Healthcare is not and cannot ever be a free market. There is a massive asymmetry because everyone will need it at some random point not of their choosing and when they do need it the consequences of not having it can be death.

Healthcare is not a fungible good. If you have aggressive cancer you can't just switch to a phsychiatrist because he/she is a "cheaper good" than your oncologist. Delaying purchase of your heart surgery may mean death.