If you are a citizen your by definition an Italian regardless of where your ancestors originated from or where you where born. This is after all how it works.Modern day international football is dumb. I would rather Italy lose every game until the end of time than see it packed full of foreigners like France, Holland, Germany and Belgium.
In case you didn’t know Italians or rather the people living in modern day Italy have always been mixed in terms of culture, ethnicity and those also genetically.
There no such thing as a pure anything, take a bloody DNA test if you doubt it.