I’m sorry your son didn’t get into Cornell, or Wake Forest, or any of the other schools that rejected/wait listed him. But I don’t think he was competing with international students. His competition would have been more regional. There are a lot of accomplished kids in the US, and it was a tough application season.
I wish people would quit blaming their disappointing results on some “other.” Kids with marginally lower stats must have gotten admitted because they’re an athlete, URM, poor, or whatever the latest flavor of shade that’s being thrown. If you’re going to knock other people, at least try to pick some who were in direct competition with your son.