This is the first time Disney fully pulled a promotion. You could, almost always book something if you adjusted your dates by a day or 2 and were willing to accept your 10th choice for resort and your last choice of room type.
Disney had the right to pull it. Guests have the right to be surprised, shocked really.
I'll speculate, without any evidence, Disney got concerned with food costs. Tariffs are outside of Disney's control. Will the tariff end up being 10% or 50%? How much will the labor costs go up for US producers? Assuming they can even find enough employees to replace those arrested and sent to foreign prisons.
I'll also speculate the guest mix was skewing to 4 Guests per room.