It seems other than Real Madrid, Arda Guler got an offer from Barcelona because he is a young talent and surely he can be a good investment for them he joins there, but Arda Guler rejected the offer from Barcelona and it seems Luka Modric said he will get retired in the next season and Arda Guler can use his number for the next season it was the reason for Guler to join Real Madrid.
Also, Barcelona wanted to hire this player and let him play and stay in Fenerbahce for one year maybe that's why he rejected that offer from Barcelona and joined Real Madrid instead.
https://onefootball.com/en/news/luka-modric-wants-to-give-arda-gueler-his-shirt-at-real-madrid-37802952I don't think about difficult for getting regular position make Arda Guler join to Real Madrid after rumor linked he will move yo Barcelona. Actually, Barcelona less potential midfielder than Real Madrid after signing Jude Belinggham and right now have many potential midfielder. Arda Guler choose Real Madrid because higher transfer fees than Barcelona and possibility with higher salary received from Real Madrid than Barcelona.
Have rumor with Arda Guler will not automatically in senior teams, he will start on junior level firstly but depend how possibility get chance if any midfielder have absent.
a little surprised by the transfers that Real Madrid is currently making, they now have a lot of midfielders, and if you look at the midfielders they all have the same quality so of course there will be fierce competition to be able to get the main place.
Arda Guler is an investment for the future, he is only 18 years old and Real Madrid does this a lot, as was done with Martin Odeegar and now Arda Guler is back like that again, the chances of him succeeding at Real Madrid are slim in my opinion, but this is enough to be a stepping stone in order to develop.