There is a new era started for Napoli with the departure of Spalletti and the arrival of Rudi Garcia. Rudi Garcia isn't a manager whose career is full of achievements maybe. But he made Lille the Ligue 1 champions in the past. If he builds up a good level of chemistry with his players at Napoli then they can still be in the title race next season as well.
But this is mostly dependent on whether they lose their most important players or not. Osimhen's price tag must be around 130-140 million euros. This is a really huge amount and even the richest teams think twice before paying this for him. If Napoli manage to keep Osimhen for next season then they can really be very competitive once again.
I think Rudi garcia is familiar with the atmosphere of Serie A because he has coached Rome before. I think a big challenge will come to him next season because Napoli's status is the reigning champion. With his coaching style, I'm sure he will be quickly understood by Napoli players. Well, one support for him is to keep his core players from leaving for other clubs in this season's transfer window, such as Osimhen and Kvaratskhelia.
Next season Napoli will be one of the teams that is highly reckoned with in Serie A after their good performances this season. Even next season Napoli will be quite busy with a busy schedule and I think Rudi garcia should understand this from now on where he has to buy better players to support himself in helping Napoli retain the title next season.