After playing in Saudi Arabia for a few seasons, he could return to Europe with his transfer certificate in hand. He may miss his prime, but he could experience Europe once again as someone who has earned more money... If you ask me, I would say this is undoubtedly a bad career planning, but life sometimes forces us to do what is rational...
By the way, I haven't seen any official announcement about Osimhen and Al Hilal, but there are reports in the media suggesting that the chances of this transfer happening are very high...
Osimhen has made a big mistake because when he was still with Napoli, Chelsea was very interested in his services at that time but he rejected it. That's what made him join Galatasaray which reduced his fame because he played in the Turkish league. But this season he stole the attention again because he got an offer from Al Hilal with a very large salary, I think he should accept it because this is an opportunity for him to earn a lot of money.
But we'll see, whether Osimhen will take the opportunity to earn a lot of money or he will stay in Europe to realize his dream of getting a prestigious trophy in his career. I see Manchester United also want to bring him in, but their hopes are so small.