Age have nothing to do with Ronaldo , he is still very active . The reason why maybe much clubs are not interested in buying him is because of the high amount of money to sign in him. This season Ronaldo have not played football in a full match compare to last season that is why he has not done much.
Ronaldo said he was going to retire at the age of 40 that was from his past interview with Piers Morgan. He is the most ambitious footballer ever in history of football. He has said he will love to play with his son in professional football. And also, he has a lot of records to protect due to the activeness of Lionel Messi. He thinks he still has a lot of years left in professional football. I do not see him going to Saudi Arabia. And I am very sure he will sign for a top team in Europe. Possibly, Napoli.