I doubt that, as do the times higher education rankings on all but perceived reputation - i.e. US universities are more "famous" in that when scholars were asked to name 15 good universities, they often included US ones.
Although some US universities are highly rated, and mostly in the top 10 for certain metrics and subject matter, they certainly are not "undoubtedly the best".
Thats not to say they are bad, but clearly your judgement is clouded.