what have they done to shape the Argentinian society and make it the way that it is ?
Logically, you look at who Gauchos are, what are their traditional cultures, maybe their history etc. Then you take another look at the current Argentinian society, look for similarities between them and the Gauchos. There are quite a few, depending on your perspectives.
It is not hard to observe Gaucho influences on Argentinian society by comparing them, that insight should answer your question.
Hope that helps.