Cannavaro had an impressive record in the years leading up to when he won it as well. Virgil's barely got going. Nice to see a defender being mentioned because they're usually overlooked in general not just in the big awards.
These days it's just an honorary title from a city to one (or a group) of its own to say well done for an achievement, like some of the Olympians e.g. Chris Hoy, Jess Ennis. In ancient times it meant you could graze your sheep anywhere in the city....