for now Osimhen is Napoli's mainstay player and the reason Napoli is giving such a high price is because they really don't want to really sell him and if there is a team that is willing to buy at a price that has been set by Napoli, they have already targeted other players who can still help Napoli dominate the standings next summer. so don't worry too much about Napoli's future in the summer because no one really wants to get Osimhen at such a crazy price and Napoli always has a strategy and a way to stay the best in Serie A.
What Napoli is doing is one of the efforts to keep themselves strong in Serie A next season, because such a high price can also be for two other players whose quality is not much different from Osimhen. This means that Napoli is quite smart in managing this strategy in terms of protecting its players and also in terms of maintaining the strength of its team so that they don't experience a slump in the next season. So this is one of the wisest thoughts for Napoli.
Currently there is news that in the end Osimhen will extend his contract with Napoli because seeing from the current conditions where Madrid did not move and Manchester United did not make an offer for him, it is indeed likely that a contract extension will be made by Osimhen.
Actually this has been awaited by Napoli too because seeing from the season before it ended they had offered a new contract for this player but were still held back because at that time there were quite a lot of clubs who wanted Osimhen's services, but when the price set by Napoli was quite high then one by one the clubs who wanted Osimhen to leave.