It’s just not really true, when I broke my foot (as a Canadian) I didn’t really consider an ambulance, because I didn’t need stabilizing or healthcare on the ride over and i probably didnt want to go to the ER over UC during the height of covid. I just hopped in an Uber, which got me there faster, why would i want the whole gurny and flashing lights. There are certainly people who would have called an ambulance in my situation (and plenty of situations where a broken foot warrants an ambulance too) but there are also plenty of rich Americans who would do that too.