The difference is that in France public hospitals do not overcharge public insurance, as private hospitals do in the US with private insurance and probably Medicaid too. Also, public health insurance is not a for profit business that aims maximizing profit at the expense of sick people. It's also easier to become a doctor in France vs. the US or get an equivalent degree from an Eastern or Central European country. France can also easily import doctors from other European countries, which lowers healthcare costs. Also, as a healthcare professional you are not as exposed to litigation as in the US. Canada seems to do ok with a very high barrier of entry for doctors however, probably because they have NPs which handle part of the doctors' workload.

As for education per percentage spending paints a distorted picture. A more thorough comparison is needed accounting for the cost of education, population size, absolute numbers as opposed to percentages. Otherwise I agree that the US has fancier, more exclusive higher education institutions and that professionals with a degree are paid much better than in France.