Italian geography is complex. There's a reason the allied forces took way longer from Naples to Milan than from Normandy to Berlin despite heavily outnumbering the Germans.
I was always super proud of the quality and maintenance of Italian highways. Somewhere around the turn of the century I stopped feeling as proud because maintenance started lacking and other countries that I visited (eastern Europe) has also built some very good roads.
One thing to notice though is that the highways are expensive.
From Rome to Milan in a small car you're paying around 60€s in tolls.
That's not a small price, especially as it is way higher than 15 day passes for all highways in some other central European countries.