Earlier quoted context omitted.
The US has top-tier cancer survival-after-diagnosis outcomes. We spend too much to get there, and other countries in our cohort would "argue" that we get those numbers in part by diagnosing earlier and that our outcomes are broadly similar, but if you're going into these debates with "the US private health care system causes cancer deaths", that's a pretty rebuttable argument.
This is a cherry picked statistic. We still have lower life expectancy, high infant mortality rates, and one of the highest rate of preventable and treatable deaths among developed countries
For infant mortality specifically, in the US we count every baby with a sign of life, regardless of the age. In many developed countries, they simply don't count too premature (under 22 weeks or 500 grams, iirc) and therefore don't consider them in the metrics. It makes for an apples to oranges comparison.
You're right on "preventable and treatable deaths" with heart disease and diabetes being the biggest contributors. The question for that comes down to "is that a result of systemic issues or individual choices?" because we can do lots about one of those.