They spent the whole season without their centre-forward and reiterated that they were a great team, first winning the La Liga championship and then the Champions League. There was only one cup missing, I think, with the Mbappe transfer, they became candidates again for all the trophies that can be won next year.
Xavi has left the Barcelona side and it should only be a matter of time before the team announces new transfers. Yes, first of all, Barcelona needs new players to organize its fragile defensive line.
You say they don't have a striker, but you forget the Bellingham factor, who scored in every game at the start of the league and brought them wins. In those games Bellingham always played like a striker and went inside the penalty area. Later, when Vini Jr. returned, he made a significant goal contribution. Joselu, who nobody liked, who was seen as a backup striker, worked wonders. Rodrygo and Diaz scored goals. Real had no goal problems. They had a very strong offense even without Benzema. They will be the favorites next season too, because it's still unclear when Barca will overcome the economic crisis they are going through.
So that's it, when they don't have a player who can be relied on as the spearhead for scoring goals, other players can replace that role very well. Even Jude Bellingham, who has just joined, has adapted well and has become the difference with the goals he scored at the start of the season. This is an advantage that Real Madrid has, because their players have good abilities in scoring goals. so that even when they are without a striker they can still be productive in scoring goals.
The good teamwork and chemistry they have really works for them. Even when they have a lot of young players, they can immediately play well with their seniors. I don't see any selfishness between them, even though if we look at them they are great players. Coaches can be good at suppressing selfish attitudes from players, so that is also one of the factors that ultimately led them to the success they have achieved now.