The fact about Xavi Alonso is he is still a young coach and he is not experienced a lot which means this coach can even have better performance if he gets experienced and starts working in some other teams.
Maybe that's a good reason to say other teams like Real Madrid and even Bayern Munich are going to show even more interest in hiring Xabi Alonso soon.
For top clubs, to some extent, the main requirement for a coach is that he does not spoil anything in the first place. It is difficult to expect (with such a composition and dominance as, for example, Bayern) a result in the national championship other than the title. The figure of the coach is not very important here. On the other hand, in the Champions League there are no guarantees even for the top team and top coach (for example, City and the paper best coach Guardiola). Therefore, if we think logically, there is nothing wrong with hiring a young coach (who has already proven himself).