I stopped playing soccer in 2005 and I'm an American and we were never taught to dive or fake an injury and I played high level youth soccer for years and my friends play soccer in college and you didn't see players doing stuff like this. I swear that for all the years that I played I never saw a single player feign injury or blatantly/clearly dive to gain an advantage. This was back when there wasn't really YouTube or social media or much soccer on American TV so most of the American kids I played with and against didn't see this sort of behavior and we had essentially no concept of it. The first real run-in or experience that people my age who played soccer had with diving was probably Cristiano Ronaldo when he came onto the scene. Before him, I can't remember seeing hardly any players diving but the fact that he has been a massive player and receives lots of attention maybe is what led to him getting negative attention for theatrics and it also may have inspired youth players to behave like that though most youth players don't behave that way in America. In other countries you tend to see behavior like that more.

America has gotten very diverse as well so I don't know how some ethnic groups or races play or behave or what they might be taught by coaches or adults but when I played diving/faking was basically non-existent.