Napoli won the scudetto last season because Inter Milian were too focused on winning the UEFA Chiampions league. I wouldn't blame them for channelling all their energy on the UEFA Chiampions league forgetting they had a scudetto to win, maybe it was due to how important and valuable winning the UEFA Chiampions league trophy is over the scudetto. I think Napoli might win it back to back if care isn't taken serious due to how fragile inter Milian team is. Inter Milian has completely lost form after the sudden defeats they suffered in the hands of PSG in the last concluded UEFA Final. Ever since then, Inter Milian players gradually starting experience decline in performance of which I think will affect their chances of winning the scudetto this season. I think since Napoli now has Kelvin de bruyne on their team,it will boosts their chances of becoming the winner of the Italian scudetto this season. Anyway let's wait and see how things will unfold between inter Milian and Napoli in regards to winning the scudetto.
While it is not impossible, Napoli will have a lot of hard time because they are a new team basically. They bought so many players that this season they will have a lot of different players on the field, and that means it is not the same team that won the league last year. That is why it may to be that simple, and it could cause them a lot of trouble, and we may not be a lot of people who end up with a lot of growth.
This is why the best way to move forward would be just hoping that things will grow better and we can definitely make it work for all of us. If we can see Napoli act a bit better, like adjust together better, then they will win again, but if they fail and chemistry feels off? Then they are going to end up with a lot of losses.