I think a player like Osimhen needs to play in a better team. Can you become the best player in the world by playing for Napoli? This is almost impossible.
I think a player at the age where he needs to show his highest performance should be in a team like Arsenal or Bayern. It has a value of over 100 million euros, but they are not using its potential right now. I think there is no need for such a player for a team that cannot even be among the top 3 teams in the Italian league
Actually, it is not impossible if he becomes the best player even though he plays at Napoli, we know that in the past Napoli also produced many stars, but at the moment it is a little difficult because Napoli as a whole has experienced a decline which ultimately makes us doubt them. Last season they managed to win the Scudetto title but this season they are very different and have now been thrown out of competition at the top of the standings.
I agree with you that Osimhen should seek new experience in a new team that is in a more competitive league. There are several teams interested in him, but Napoli have set a price of 100 million. In my opinion, this is still quite feasible because Osimhem's performance is actually still good even though the team as a whole has experienced a decline. So far, I haven't heard of anyone making an official offer to Napoli, but according to rumors, there are at least 2 teams that want to bring Osimhen from Napoli for next season.