Try having a pre-existing condition before ACA - no one will insure you because you're too expensive, or your premiums go ridiculously high. Think about that. The people who need insurance the most were denied it - this is perfectly in line with market forces of course because its cheaper. The other alternative is to believe healthcare is expensive for everyone because the healthy subsidize the ill, but oops if you're ill your costs are astronomically high anyways and insurance companies will fight you tooth and nail over expensive claims, so that doesn't hold much water either.
If you want to talk data look at spending on health care vs outcomes [1]. If market forces were working so well maybe we wouldn't spend 2x - 4x more than other countries with worse life expectancy to show for it? We can argue over where the money is going but its clear theres a lot more of it going in for worse outcomes coming out than most of the world.
Honestly, seeing that if you don't see ANY contradiction or perverse misalignment between the ideal goals of a health system and the current system, you must be a very healthy guy.
[1] https://ourworldindata.org/the-link-between-life-expectancy-...