Your hypothesis straight up assumes that a) Americans have the best possible education required for the work (we don't; functional illiteracy has never been higher in the last few decades). And b) Americans are the most fluent in English (again see a.).
Even if the above assumptions are true the set of Americans who are qualified will be completely outnumbered by, say, even 2% of qualified people from a huge population like China/India/etc.
Even if the above assumptions are true the set of Americans who are qualified will be completely outnumbered by, say, even 2% of qualified people from a huge population like China/India/etc.