Do you think Xavi alone would do anything with an average team/unbalanced team like Argentina? Dont even need to hypothetically bring him to Argentina to make that point, he has played in a mediocre Barca and Spain in big part of his career, and he didnt "step up" as many say too easily. Not realizing the obvious of what a team game it is.
Argentina NT is a fuck up untattered joke of a team after another with new coaches all the time. Expecting one player to magically fix that alone, even if its the best player in the world, is missing the obvious. Huge difference playing with that and the best team around, not just quality, but most teamwork oriented with a particular style that is infused to whole squad for a decade.