I know that UEFA cannot sanction any club in the Arab because it's not in their jurisdiction. But I believe the level of conspiracy in football. If they cannot directly control, they can indirectly influence. If they cannot indirectly influence, they can also regulate the clubs in Europe on how to sell to Arab.
It is correct as you said that this wave of buying expensive players will not sail for long. If you keep investing without an equivalent return of investment, that type of investment is not always sustainable. They Arab club owners will soon get tired, maybe their next move will be to buy clubs in Europe.
FIFA now feels threatened by Saudi Arabia finances, because Saudi Arabia is better able to attract big players. Of course this makes sense because FIFA invests more in European clubs, while from a player's point of view, it still prioritizes finances where if someone values more than what European clubs have to offer then that is their choice. Don't blame the Saudi Arabia Club because this is where European Clubs are challenged to compete with the world of finance. There is no need to talk about the phase of defending European clubs, after all, currently big clubs have entered Saudi Arabia's finances, which cannot be matched by European businessmen who invest in football. Manchester City, Newcastle and PSG are the biggest right now, and look how fast they are growing?