Why? That hydrogen most likely is created with fossil fuels, you don't avoid emissions. Actually, you will create more because the energy density of hydrogen is lower than the density of diesel, mostly due to the heavy storage tank. In other words, you need more energy per mileage to move the trains because the weight of the trains is heavier which leads to more emissions.

I don't like these in-the-grand-scheme-of-things-everything-is-the-same. There is a difference between emissions from a power plant and emission from diesel cars in densly populated cities. Just step outside.

In the grand-scheme-of-things the universe will cool out either way.

I think a lot of people are missing the point. A higher demand for hydrogen will incentivise companies to improve the production methods for hydrogen, hopefully with a more conscious effort to keep it green, i.e. Improving electrolysis methods.

Nobody is claiming that all hydrogen is greener than diesel, the point is hydrogen has the potential to be vastly greener than diesel, and the best way to explore that in a capitalist society is to increase the demand for it.

A small disclaimer, I know nothing about hydrogen.

With the steady uptake of solar panels on private homes and wind energy, it is not too far of a stretch to envision hydrogen production whenever there is more energy returned to the grid than needed.

Upvoted for honesty