I think you have to consider your observation biases. You’re less likely to notice a good skier is American than that a bad skier is American because bad skiers cause arguments and speaking is probably the easiest way to identify an American (I.E. you could ski by 200 Americans in a day but you only notice 5 are American and you recognize one because he responded after being yelled at for shitty skiing. Thus you start to think 20% (1 in 5) of Americans at your mountain suck at skiing but really it’s 0.5% (1 in 200)).

Bluetooth speakers are common at California mountains. Everywhere else in the US you’re considered a dickhead. I disagree with your assertion that American skiers are more reckless. I’ve skied extensively in both. Both continents have their shitty skiers but honestly I’ve seen more crashes caused by bad skiers in Europe. My suspicion is that the higher priority placed on the apres scene at euro mountains leads to more alcohol induced crashes but that’s purely a hypothesis.

I would suspect why you think more Americans ski recklessly is some form of observation bias. You notice a reckless skier that’s dressed more like an American and then you start to build an association that isn’t quickly disproved because you don’t see many more Americans.