I saw a few snippets of the press conference where Arda Güler was presented as a new player of Real Madrid and there he said he wants to become a legend of the club. I did not know that player before but he is definitely not lacking confidence lol. I think though that he will have a very hard time to have any playtime at all, as you already said.
Transfers like that where very young players (let's say younger than 20 years) directly join one of the absolute top clubs like Real Madrid, Manchester City or Bayern Munich have not worked out that well most of the time in the past. I think in general it is better to first go to a tier 2 club for a few years and then join the absolute best clubs.
there is nothing wrong with Arda Guler accepting an offer from Real Madrid even though he is still too young to join a top team but I have no doubts that Arda Guler's performance will continue to improve once he is in the right team. we'll see like Haaland when his talent develops and gets stronger after being in Dortmund.
young players who already have talent and are able to join big teams will certainly be trained slowly to improve their performance to be better. who would have thought that Arda Guler would become stronger after joining Real Madrid.