Barcelona doesn’t deserve to be on the list, in my opinion, because they are not in good shape.
People who think Barcelona is strong definitely a Barcelona fans that can't judge something base on objectivity, similar to Manchester United fans. 
Kevin De Bruyne is a very important player for the team and Manchester City are lucky to have him back in training. We can say that it was a generally bad season for Barcelona. Even if we see Guardiola come to Barcelona as a coach, I don't think anything will change because Barcelona is problematic in other aspects. Without improving the financial situation, they do not have much chance for long-term victories.
Barcelona is a failed team after Messi's left for Inter Miami, the socios aka Barcelona's supporters need to sell their team to the rich person. So they will have money to rebuild the team by signing popular players.