Rising costs of healthcare are also a big issue in other top-wealth countries, and for better or worse, the US also does cutting edge health science that other countries dont get close to.
I find the comparison country vs country to be valuable, but somewhat limited. The U.S. is unique in a lot of aspects.
For example in argentina(i know, not rich country but hear me out), that has public healthcare, healthcare spending per gdp has been cut in half in the last couple of decades: mostly because private healthcare ate up the market. Hybrid markets are a reasonable compromise.
The US is also not a free market of healthcare, it has the worst of both worlds: highly regulated, intrusive and punishing state, with proteccionism and quotas.
To this day I still believe the #1 healthcare policy issue is with the state's intervention. It is the FDA that makes pharma expensive, it is H1B quotas and medical licensing requirements that prevent foreign doctors to come to the US, it is Medicare that puts fee-for-service, it is the state that makes malpractice costly, etc etc.