Pep Guardiola has made his name as a coach who has a brilliant history as a coach at Barcelona and also as a former Barcelona player. He has contributed many trophies to Barcelona during his time as coach there. So it is impossible for him to dare to return there because it would potentially ruin his own good record there. Because being a coach at a club that has financial problems is not an easy thing. Only a handful of coaches are able to bring a club that is in financial trouble but can still win a championship trophy. And actually Xavi is also a good coach. But we know that even Xavi has to hold back to be able to get good players. Even the condition of Barcelona's front line is not good enough after Lewandowski aged and was no longer productive. So Barcelona could only borrow a player from Atletico Madrid, namely Felix, to cover this problem. And yes this is not an easy thing for a coach.
Perhaps it is rare for a coach to still be able to bring a team to the best when the club's financial condition is not good. But as you said, Xavi Hernandez has basically fought well and was able to make Barcelona win the title in Laliga last season. It's just that last season Xavi was unable to bring Barcelona to qualify from the UCL group stage and also failed in the Europa League. So I personally suspect that last season Xavi wanted to focus more on Laliga. And it worked. but this season it seems that Xavi will be serious about the UCL. Although many doubt Barcelona this season. But I think the chances are pretty good to get through from the round of 16. Because Napoli are also not in good form this season. In fact, it is much worse than Barcelona, which is still strong in 3rd place in Laliga. Meanwhile, Napoli is currently slumped in 9th place in Serie A. So Barcelona should have a less difficult opponent in the round of 16.Pep Guardiola might indeed be much better than Xavi but it seems impossible for Pep to come back to Barcelona. Because he is the type of coach who wants to set a new record at a different club.
And about a coach who can continue to produce good results even though the club is experiencing financial problems and is even experiencing a lot of problems. Starting from sanctions received by clubs, even player injuries and sanctions against players. Actually, there are coaches who can keep their club's performance good. He is Allegri at Juventus.
