Maybe in the little thought experiment you're trying to conduct it does, but not in the real world. There are plenty of other variables at play.

X knows that if they need trucks and Ys are in use, then people die and they'll get blamed. They know that local trucks will respond faster so fewer people die.

In one off emergency situations in the real world, people actually help each other. We're not just a bunch of ideal game theory pieces in some amaeteur economist thought experiment.