Why are you so sure Osimhen will become a superstar at Real Madrid?
I have no doubts about Osimhen's quality, he is playing very well, big clubs really want to sign him. I don't want to speculate about Osimhen future if he moves to Real Madrid, there are so many players who fail to shine after moving to a new club. Who would have thought that Hazard would fail at Real Madrid, Coutinho after moving to Barcelona and Lukaku when wearing a Chelsea jersey.

He needs a club that gives full trust to him, his development while playing at Napoli is much more improved than before. I think it's better for him to stay at Napoli than to move too quickly to a big club that may not be able to give him regular minutes.