I don't think, Napoli will be able to win this Italian league title next season because one of their potential striker is willing to join premier league team next season to showcase more skills in a way he will have a good record from the team like the way he got a good record from Napoli by helping the team to lifted Italian league title this season. I believe, Napoli management will do something fast that will make the team stronger even though they will not achieve next season title, they can take second or third position from the tournament. Next season will going to be a tough season for Napoli, because it will be difficult for the manager to get a young talented striker like victor Osimhen in this summer.
While osimhen played a huge role in Napoli trophy win i don't think we can say that they won't be able to win the serie A because there is no team that are ahead of others in the serie A so there are a few who can win the title such as inter juve milan and napoli, even teams like roma and lazio might have a small chance this is how close the teams are in term of level i think as long as napoli team secure a decent striker they have a fair chance to be champion again.