Even with the contract extension for Osimhen and new manager, I still think if there's a club willing to sign him right now, he would leave without blinking, mostly when it is to a top flight club like Real Madrid or Chelsea which has been rumoured to want to sign the striker..
He is a definitive player and a striker of class who just won the African player award. There's a lot still for him to prove about his worth and value and Napoli has only seen just a fraction of the potential he has to offer, hence why he should transfer out of the club in the January windows if possible.
So far, it seems still a rumor about his contract extension. There is no official statement from Napoli to extend his contract in the near future, right? Even I didn't read the news about Osimhen's official statement that he wants to extend his contract. Osimhen still has a contract with Napoli until June, 2025. It is not urgent to extend it now.
Sure, if there is an offer to play in a bigger team like Real Madrid, no doubt Osimhen will try to consider it. Osimhen must realize that he needs to move to a bigger if he wants to achieve a better career. Real Madrid is the right team for him if he has the intention to UCL trophy. It is a very small chance to win UCL trophy with Napoli.
Anyway, it is cool that Osimhen could win African player award. This probably increases his market value.