Healthcare and college are "Baumol cost disease": because they depend on skilled workers, much of that is the same as "American salaries are higher than in the rest of the world", and unlike manufacturing or software (+) you can't outsource it to lower-wage countries.

(+) there still seems to be a massive wage premium for "being physically in a San Francisco office" even if most of the work is being done by an AI, which cannot be sustainable

Bit for bit, internet access is cheaper in America than it is in Canada or Australia.

Canadians like myself have ~40% of our provincial taxes spent on healthcare, so in my case about ~8% of my gross income. Somewhere in the tune of $20k/yr. While I was living in Seattle and filing American, quite a bit less of my gross income went to healthcare. Just food for thought.

Internet access isn't particularly expensive in the US.

Healthcare, education, and housing are expensive in the US for the same primary reason: political interventions that simultaneously subsidize demand and restrict supply.

You can add Pre-K education to that list. It's on par in terms of costs with sending your kids to college.

This is why people are moving out of the US in droves, the universities are empty and nobody goes to the doctor.

Internet access sort of has a reason: the US is geographically huge and more sprawled out. But that's not enough to explain all of the difference.