Basically, if Juventus didn't drop points then Juventus could have been a tough competitor for Napoli but unfortunately, Juventus lost their ambition to catch Napoli because they had a bad case. But even though Napoli can dominate Serie A last season, at least I don't conclude the other teams are bad because after all, such inconsistencies are very natural. Also regarding Roma and Inter for me both remain good because after all, when one team cannot get maximum results in the local league then of course they can be more optimal in other competitions or tournaments. So yes, Roma and Inter still had good performance and results last season and for next season, of course we will expect a more competitive competition in the top zone.
I see the difficulty of predicting the favorite club to win in Serie A, because normally we predict the winner from the team's performance. Meanwhile, another fact that is happening now is the case scandal that ensnared Juventus management which resulted in deducting the points obtained from the results of the match. So how well the team performs does not guarantee a club will win if the management breaks the rules. Napoli were able to dominate Serie A last season because Juventus were being hit by problems, next season history like this might happen again. So that makes it very difficult for us to predict the strongest candidate to win the Scudetto.
If next season goes as normal Inter Milan, AS Roma, Napoli and AC Milan are at the forefront of winning the Scudetto, I personally favor AS Roma because of Jose Mourinho.