They just haven't againts yet ATM or RMA. because only those two teams from Madrid are always competitive to be Barcelona's rivals in the last 10 years. If the barometer is victory against middle and lower teams on the table, then you won't believe that La Liga has 38 matches.
Unless Barcelona wins against Real Madrid and Athletico Madrid, the possibility to be La Liga Champions will be greater because they managed to get points from the 2 teams.
It is true, points are calculated for all matches, how consistent in 38 matches, but at least winning from that two teams is something that can increase team morale.
In one season they have to collect as many points as possible to be able to become champions in La Liga. However, in a competition there are teams that are considered tough and will be a threat to them, in the context of Barcelona, Real Madrid and Atletico Madrid are always their threats.
However, that does not mean that you have to underestimate other teams, be it top teams, middle teams or even bottom teams, when they meet they have to make sure they bring victory. Because sometimes we focus too much on the teams at the top, then we forget about the role of the middle or bottom teams. And we have seen a lot that they can also make top teams fail to get points, so don't underestimate whoever will be their opponent.
At least if they manage to beat both teams from Madrid, their players' morale will increase drastically. But this is a long competition, squad depth is very important. We don't know whether all line ups are ready to play throughout the season without injury.
We see how the Premiere league has been going in the last few seasons, squad depth is a determinant of team victory in the tough competition and competition schedule and Man.City has it all.