The mechanics and logistics of steam powered vehicles make them impractical. Who wants to go out on freezing morning fill the boiler with water (you did remember to drain it so it would freeze and break, didn’t you?), start a fire. wait half an hour, then refill the boiler every few miles and add more fuel? Yes, there are automatic water and fuel feeders, but they add expense and complications to the equation.
The reasons the railroads were eager to switch from steam to diesel electric were because the steam locomotives were a high maintenance item that were in constant need of work and they were dirty.
What are they going to use for fuel when diesel and gasoline are banned?