I wonder how?
All they can do is make empty threats. I don't think they don't have any guts to boycott World Cup at any cost. PCB would go bankrupt if they do this, doesn't matter who is the chairman. Don't forget in this 2024-27 cycle they are set to earn a minimum $34.5 Million every year, that's $138 Million in just 4 years. Do you think PCB wants to lose this share?
Pakistan doesn't contribute much to the ICC revenues, yet they are given a much higher share when compared to the other boards such as SLCB and CNZ (around $27-28 million each per year). If population is the criteria, then Bangladesh is also having a similar population and they are only being allotted $26 million per year. I would say that the PCB received a good deal for revenue distribution for the 2024-27 cycle. If they want to pull out of the world cup and lose that money, then it is their decision. ICC can re-distribute that amount to the associate nations.
For the argument let's even forget about the distribution because on principle I believe every full test nation deserves its share despite they are contributing anything or not.
In all Asia Cup drama, you'll notice that only PCB is making a noise every week or so, and BCCI stopped reacting to it completely.
Also, Recent news is the new PCB chairman is not happy with the hybrid model and he'll raise this issue in front of ACC as he believes it should be hosted in Pakistan,