I'm not a fan of Real Madrid, and I must say that you are a bit harsh with them. It's a fact that no matter which team it is, the arrival of a new coach brings changes to almost everything, from tactics and training aspects to faces and players who will follow this plan. Real is in a changing mode overall, and it's too soon to say that Xabi won't succeed. Of course, Real is Real, and the expectations are always high. However, every team needs time to be better, and time is the same for everyone. IMO Real will be among the favorites for this season and LaLiga, as it always is.
Predicting anything about any team currently is too early because most of the coaches are doing things for next season, and they are surely having better things in future Real Madrid is having change of coach and Xabi Alonso needs to understand few things with players adjustment is also important for him.
PSG used tactics like Barcelona and have big success in semifinal which give them good success they will learn their lessons from this defeat and their defense which is long time problem going to be better because without any improvement it's not easy for them to have better results against big teams. Too many big players with all on same level it's never been easy to have adjustment while few are surely needed more playing minutes, but coach surely have to check all possibilities for having better results.
Under the guidance of its new coach, Xabi Alonso, or often called the red beard, Real Madrid is trying to build its new project. So we will see more player changes in this transfer market, where at this time Real Madrid has released two of its players, namely Luka Modric and Lucas Vázquez, and also the latest rumor is that they will also release Rodrygo. Meanwhile, I don't know for sure about the rumors of players they will bring in, but with many vacancies especially in Real Madrid's midfield, of course to face the next season they will bring in more players. In addition, in yesterday's match at the Club World Cup, when Madrid was willing to lose 4-0 to PSG, this showed that there was a slight problem with their back line, the absence of D Huijsen due to a red card in his previous match, his absence on the field really affected Real Madrid's back line. And to avoid a similar situation when the season starts, Real Madrid must bring in another defender to further strengthen its backline.
As for PSG, I don't have much to say about that club. They are currently in their peak, have a strong foundation, and still have enough dominance to defend their Champions League title.
This is the beginning of a new era so fans should be patient with Xabi Alonso I many fans online questioning whether he's the rightful person to lead them to victory again and I know that's cause of the lose to PSG in the Fifa club world cup. If Xabi didn't prove himself in Leverkusen I don't think Real Madrid would've given him a chance to manage the club they should be too quick to last him before he's even start it's a process and I believe Xavi would be working on getting his current team to do better.