How did that happen? Why? No explanation, no hidden references, no hand-holding to any possible conclusion, no reference to the cost of a social change so complete. Unless you actively engage and critically think through what you are seeing and it's implications, you would never know.
In the hands of any other director it could just be laziness. Oh look, he's set it in Argentina, but they're all just like American kids. He couldn't even be bothered to include any local references. He could have at least hired local talent right? Taken advantage of the setting? But no, the fact the setting is this way is the actual point.