I have a bold prediction that Napoli next season won't even be in Top 4. I expect them to lose a lot of points in begining of the season. Everyone will play with more fire against them since they are champions and with possible departures of key players I see that happening.
I'm not a fan of Napoli as I read that their coach manager resigned and also some of their players were sold to other clubs and out of contract, but I can't predict the future because we don't know in the future Napoli will buy other great players or not. next season, juventus, their competitor, was hampered because of a case that made them play inconsistently so that they fell to 7th place.
I am also sure that the completion of the case facing Juventus will make them pay for their failures this season so that next season they may also have new players to make Juventus rise from adversity.
Because Napoli have been able to consistently compete in the top four in previous seasons, so next season I personally will remain confident that Napoli will still be a team competing in the top four. Although indeed, it seems certain that in the next season Napoli will have a new coach and also, with key players who will leave the club, but I believe this will not make Napoli so weak that it cannot compete in the top four.
In football, it often happens that certain good players wouldn't stay with one club for so long without being sold or loaned to other teams. The goal of selling out the top players on a team is to increase revenue for the club while also buying fewer replacement players.
I think Napoli will know the best course of action at the start of the next season given the situation it has found itself in, which includes losing its coach and selling its star players. If they don't have any plans to replace them or already have other top players on the squad, they can't just sell their star players like that.
We can't begin to make predictions regarding Napoli's chances of reaching the top table until we have seen how they play in a few of their games by the next season.