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.