Look, American cheese is awesome (I am not talking about Kraft singles which are a pasteurized process cheese, which, tbh, is fine fo like, grilled cheese sandwiches with tomato soup) but no, it isn't the best. I would say that "the best" is a use case specific thing. Like, cream cheese is awesome for cheesecake ,, where as an aged sharp cheddar would kinda suck in that scenario.
There is no best cheese, however, if there was, pepper jack wouldn't even live in the same zip code as that cheese.