That they may be different from rest of this class of clubs. And at the moment better off. Decision to take what might seem a PR optics hit may as well pay off considering a lot changes for the player's camp since the moment they originally request the clause. He could turn around in 2-3 years and say 'well, actually, I won this much here, why would I leave'?
Besides for oil clubs player commitment is not so important, they can always spend more to replace and remain where they want to be even if not setting records like Haaland's current stint is. Pep staying is much more important for where they want to be as a club.