It was a decision they had already made because they let Osimhen go. Since the change of coach, they were no longer interested in Osimhen because they were more concerned with bringing in Lukaku which they finally got.
Osimhen must be able to show that he can compete and make a big contribution to his new team now, because if he can show something good, then there will be many teams interested in him and willing to pay a lot. Unlike now where many teams are still hesitant to spend big money. He must improve his performance first if he wants to get a very big salary, unless he wants to go to the Saudi Pro League.
Osimhen has now got a team that can make him more confident and make him play as a core player in the new team. Osimhen seems no longer needed as long as the new coach replaces him with Lukaku so he has to adjust to the new team, Osimhen needs a good performance to make a name for himself as a player that the team needs in a core position with a more aggressive physique when playing in matches, I doubt if Osimhen wants to go to the Saudi Pro League because there is still a chance to play in the team he is currently contracted with, hopefully Osimhen can play well and win League with success in 2024/2025.
If we look at what actually happened to Osimhen and Napoli, of course the problem arose when Osimhen stated that he wanted to leave after PSG interest in him, so this made Conte decide that he wanted to reunite with Lukaku, who he had previously coached, in my opinion, if Osimhen had not stated that he wanted to leave Of course, maybe Conte will still maximize him as Napoli main striker at this time, but as we know, Conte is a firm coach and doesn't want to force a player to be in his project if the player wants to leave all this time, his move to Galatasaray is actually only temporary after He failed to go to Chelsea or PSG because in the end Napoli froze him from the current squad, so in the end Galatasaray became a bridge for him before he would leave for another team later when the transfer market opened again.