Of course some things are expensive - but there are still efficiency savings to be made; Americans on average spend more for the same health outcomes.
For example, American medicine has a culture of ordering lots of tests based on legal, rather than scientific guidance. Consider the Merenstein PSA case [1] for an example.
Increasing efficiency and driving down average healthcare costs ought to reduce insurance costs.
Still, someone will end up having to pay for a month in the ICU.
Health insurance is a way to share the risks so that nobody has to die just because they can't afford treatment. The odds I'll need expensive medical care increase every year.