There is a factor for the US effectively subsidizing these countries by having our current system. Healthcare companies make their bread in the US and get scraps elsewhere in the world.

This drives an enormous amount of innovation, and the near complete dominance of US healthcare companies in the west reflects that.

The US moving to a universal healthcare model would likely kill the lucrative US market, and while providing cheaper healthcare, it likely wouldn't make them dramatically cheaper while also having the effect of driving up costs in other western countries.

A bit like a balloon, where the profits are swelled in the US and limp elsewhere, squeezing the US will ha global effects.