Except you can extract 237 kJ/mole from hydrogen. A fuel cell is a battery and can approach the efficiency of a lithium-ion battery.
> No, you cannot use existing gas pipelines for transporting hydrogen.
You absolutely can. In fact gas companies are already planning this exact thing.
> For passenger cars, EVs today are already better than what physics allow hydrogen cars to ever be.
Your "physics" is entirely pseudoscience.