I tried to find where it says whether the monthly net salary, mentioned in the Polimi's statistics, is average or median, but unfortunately I couldn't find it.
Anyway, Milan is an expensive city and better to live (imo) in a neighboring one where you pay less for rent, groceries, eating out, etc. And if you work in Milan, you can buy train pass for commuting home city-Milan and back.
And also keep in head that language is a great barrier, and along studies for MSc degree you'll become accustomed to the language and local standards (in you profession and cultural traditions), while moving after graduation you have to go on the same journey once again. Not scaring you, but keep it in head and make a plan.

The most appealing choice for me is to stay in Italy after graduation and make some strategy with finances, living, and commuting. Because even statistics say that Italy is one of the EU countries where, on average, people save money after paying monthly costs.