Insurance that is maximally responsive to patient health changes in terms of cost (ie making healthier people pay less) ends up being an inefficient way of just having people pay for their healthcare directly.

And it naturally means the people with highest premiums are the least likely to be able to afford it (the elderly, the disabled, those with chronic conditions that make them less likely to maintain high earning jobs steadily, etc)

Not a US citizen, so a genuine question: do US health insurance companies have a track record of passing on such savings to consumers?

That has not been my impression as an outside observer.

We agree that insurance is not the right way to handle health as a product, since some people predictably need much more medical treatment than others. But it’s how the US has chosen to do it, so we have to do it in a way that works. Correctly identifying a systemic issue won’t pay your medical bills.