In my opinion, no, Osimhen is a great player. There were some issues with Napoli that couldn't be repaired, which is why the club and the team decided to let him go. It's clear that a player like that would have done very well at Napoli, but the disagreements meant that there was no continuation.
Besides the disagreement between Osimhen and Napoli, a player like Osimhen would have been eligible to move to another team if he was no longer needed at Napoli, as Napoli currently has a strong enough squad to face a more challenging season. Therefore, Osimhen's permanent move to Galatasaray is highly feasible, as Galatasaray is very fond of him, and Galatasaray is actively seeking a way to prise him away from Napoli. Now, Galatasaray and Napoli are both ready to embark on their respective seasons.
The team presidents are now expected to sign off on this transfer. If the final kinks are ironed out, we could see Osimhen's transfer very soon. Napoli has made it clear since last year that they don't want him on the team. Now Osimhen is all too aware of this fact. He had a fantastic season at Galatasaray, where he went on loan last year, and everyone seemed to love him. The fans and management loved him. Therefore, he will likely continue with Galatasaray next year.