If one considers everything spent on health insurance companies a waste, which I disagree with, one should look at the loss ratio to see how much the insurance is extracting. In the linked report, the loss ratio is 84% so the insurance companies extracted ~16%.

The comment by orwin says that 22% is spent on bureaucracy in France public healthcare. 16% doesn't look that bad.

I'm not saying US healthcare doesn't have problems and there aren't some weird practices but if you can't measure or identify the problems correctly, you are not going to fix it.