Health insurance is a muddled mess of rules, regulations, and profit-driven behavior. Make no mistake about it, the insurer's coverage decisions are driven by their bottom line, not your health outcomes. That doesn't make them bad people, it makes them corporations with a fiduciary duty to their shareholders, not their subscribers.
All insurance, including health insurance, is about pooling risk, so we're all paying for each other's health care one way or another. The only real question is what's the best way to deal with pooling risk when it comes to health care. And if the answer to that were easy, we would have done it already. One thing that many people think would make it easier would be to remove the profit incentive, but there are a lot of people who's careers depend on that. So that's not easy, either. And, there is a reasonable argument to be made that the profit incentive has driven a lot of the advances in modern medicine, which--generally--have been positive for society. So, again, it's not an easy nut to crack.