Didn't go well for South America in the 60s and 70s but perhaps, as economists are prone to saying, "this time will be different".
The fact that a handful of individuals have half a trillion dollars to throw at something that may or may not work while working people can pay the price of a decent used car each year, every year to their health insurance company only to have claims denied is insane.
This money is managed by small amounts of people but it is aggregated from millions of investors, most of these are public companies. The US spends over 10x that amount on healthcare each year.
There are lots of problems with our current approach to healthcare, but insurers aren’t charging you way more than the cost to counterparty on that contract should be.
A graph of the stocks for UnitedHealth, Elevance (formerly Anthem) and Cigna shows that they're all on the growth track for the last five years.
If a subscriber pays them what they do, and they don't have money to pay a claim declared medically necessary by a medical doctor, but do have the money to forward to a retirement fund, they are charging too much.
Most of the rest of the industrialized world seems to grasp this concept, and their people live longer.
Stock price ! profitability, but you're still correct. UnitedHealth's operations have churned out cash each of the last four years [1], as have Cigna [2] and Elevance [3]. Underwriting gains across the industry have been strong for years [4]. The only story I can think of where American health insurers lost money was Aetna with its underpriced ACA plans [5].
That said, whimsicalism is also partly right in that insurers aren't the cause of the unaffordability of American healthcare. They by and large pay out most of their premiums. (With some variance.)
[1] https://finance.yahoo.com/quote/UNH/cash-flow/
[2] https://finance.yahoo.com/quote/CI/cash-flow/
[3] https://finance.yahoo.com/quote/ELV/cash-flow/
[4] https://content.naic.org/sites/default/files/2021-Annual-Hea...
[5] https://spia.princeton.edu/news/why-private-health-insurers-...