Last season Napoli showed from the start of the season that they would be the leaders because they didn't lose 15 games in a row. Even then it was clear that the other clubs would not be able to get to the top. Of course, next season everything should change after the leave of a key player and the change of the coach. The competition will probably be high.
I would be surprised if there is no strong competition in the Serie A next season. All the clubs are reinforcing in their own way and what makes it spectacular is that no team looks ridiculously higher than the other in tera of squad quality. I think the Serie A is the only league that you can't guess two teams that will win the league next season and be 90% correct.
Juventus, Roma, Napoli, Ac Milan, Inter Milan all look like teams that are ready to fight for the league.
The top of the league might not be like it was last season where Napoli ran away with the league.