A hair over 17% of the US GDP is spent on health care. That's the highest among peer nations.
It does so because it can. It's the wealthiest country on Earth so such high inefficiencies where a lot of the money is squandered to the benefit of few wealthy and unscrupulous parties, can be financially absorbed while still delivering a system that's functional enough for its citizens to not revolt over and want to hang someone. After all, it's still better than scary communism.
Everyone has the same 100%, just distributed differently.
If Country A is spending 10% of it's GDP on 10 things, Country B cannot possibly outspend it in every category as a percentage of their respective GDPs, because "percentage of GDP" is always a 100-point scale.
If you go up one percent in one category, you have to go down one percent somewhere in the other categories.