I visited this tentative WHS in July 2019. Although I can understand that it is quite an important historical site for Italy, it is yet another very niche site and not only lacks any OUV but is in dire state of conservation.
Even though there was a military festival going on when I visited, most of the buildings inside the citadel were fenced off as their roofs were collapsing or have collapsed. The whole place needs to be cleaned from overgrown grass and weeds before it can even be compared to some of the Vauban sites like Neuf-Brisach or Peschiera del Garda. Still, I seriously doubt that it can provide any added value to the WH list.
The best view of the citadel star-shaped fortifications is from the air and since this site is no longer a military-owned place, we tried getting used to our drone here and took our first few drone photos. Once again, there are many other places with star-shaped fortifications on the list already which are far more elaborate but at least this made our short stopover worthwhile.