There are indeed some injured players in Barcelona. All those players are Xavi's first choice players so I think that also reduces Barcelona's strength. That's Real Madrid's advantage, they can take advantage of that and win big. Indeed in a big team ideally the first and second players have the same quality. But not all clubs can be like that, even Barcelona. So injuries are an unpredictable factor and this is sometimes the reason that many coaches lose matches.
Real Madrid also has injured players. Almost all their first defense is injured, starting from the Keep Thibaut Courtois. The difference between Real Madrid and Barcelona is that there is always a guy ready to step in when the other is injured. That why it looks like Real Madrid are Ok even with the injured players they currently have.
Real Madrid seems to be better prepared than Barcelona when it comes to replacing injured players. It is also important to note that only 4 players were injured at Real Madrid. and Barcelona has 6 injured players including Gavi who is a 19 year old young player with a Torn injury to the Cruciate Ligament since 23 November 2023 and may play on 30 June 2024.