Again and again Barcelona failed to get three points against teams in the bottom zone, or maybe Xavi is making some tactical and strategic experiments that are still not optimal in these two easy matches. I don't understand what happened, because even though Barcelona are relatively safe at the top of the La Liga standings, but Barcelona shouldn't have failed to win because in this match Barcelona only played against mediocre teams.
Lewandowsi also doesn't seem to have a big effort to score many goals in every Barcelona match, so it is difficult for Barcelona to take advantage of the opportunities they get to score a goal. Indeed, it doesn't matter because Barcelona still won 1 point, but if results like this continue then of course Barcelona are experiencing problems in their performance.
Even though with this draw the difference between Barcelona and Real Madrid is still very far, I agree with what you said that if Barcelona continues to show this kind of performance, it's not impossible that they will start to slip in the next game. It is true that Xavi is trying a new experiment in his formation. This can be seen in one of his players, Alejandro Balde, who fills the left winger position, even though this position is usually filled by Gavi, but Gavi, who has several positions, is placed in the midfielder this time. But it seems that the strategy did not go smoothly and instead they are very difficult to score goals.
In fact, Barcelona also found opportunities, but Getafe defended very well and managed to avoid conceding a goal. Despite the unexpected loss of points from Barcelona, they are still far ahead of Real Madrid. They are not in a position to jeopardize their league leadership.