Personally, I'd prefer to see Osimhen play in Serie A, or I hope he can fulfill his dream of playing in the Premier League. But right now, only Galatasaray is willing to pay Osimhen's hefty transfer fee. Fortunately, Galatasaray is also one of the strongest teams in Europe, having already brought in several big names in the current transfer window, including Sane, who was recently released by Bayern Munich. Sane's quality as a winger is undeniable. Therefore, Galatasaray seems poised to compete well in the Champions League.
It is big barrier for any club that want to get Osimhen by Napoli demands on transfer fee and the player demand on high wage. Osimhen is strong but his playing style is too simple and relies too much on his physical strength. It's his advantage when he is young and strong but he already got severe injuries in his career and he will become weaker physically with time.
Any club that wants to buy Osimhen and gives him high salary has to consider risk and benefit. From what has happened recently around Osimhen possible transfers, it seems big clubs in Europe see too high risk on this player and they don't want to take risk. Galatasaray is not too big club in Europe and it's not a club that can help Osimhen to enjoy the air of UEFA Champions League as well as chances of winning this title.