Part of it is that Americans consume a lot more healthcare than other countries. They take more medication. They take more cutting edge medication (e.g. it's rare GLP-1 agonists to be used for weight loss outside the US). They see more therapists and chiropractors. They are more likely to stay in private hospital rooms.

Much of this is heavily subsidized by insurance. Any drastic change in the status quo would inevitably cause pricing and coverage that people are used to be adjusted, which is why they say they want healthcare reform until it actually happens.