Real Madrid have let go of their experienced players but they have brought in worthy players in their team so maybe we don't have to worry too much about how the young players will perform for Real Madrid. Recently Real Madrid's performance has been bad and the biggest reason behind this bad performance is the injuries of important players in their club. If those who have been trying to bring themselves back for one to two seasons can fully recover from their injuries and be ready to play on the field, then I believe Real Madrid will become a very strong team again. When Real Madrid performs poorly in a season, their tendency to perform well increases a lot so we can naturally assume that Real Madrid is going to perform better next season.
Real Madrid is still a very well built team. No one will contend about that. However they will not have two experienced midfielders like Luka Modrich and Toni Kroos in the midfield. This will definitely have some impact on Madrid's performance.
We also do not know what Xabi alonso's match strategy will be like. If Madrid had organized a few pre- season matches , Alonso would have been able to experiment more with this squad. He could have tried to stabilize the team. But Madrid will not play any pre-season matches. So we are not sure yet whether Madrid will be able to maintain their performance in La Liga.
Since Madrid's squad is strong and Xabi is a talented coach, we can hope that Madrid's performance will be stable next season. However, Alonso has not been able to prove his ability so far. We saw Madrid lose by a large margin against PSG.