Serious Green Hydrogen production projects (as in the ones that already have pilot plants and have several billion in capital investments lined up for expansion

Serious Green Hydrogen production projects (as in the ones that already have pilot plants and have several billion in capital investments lined up for expansion) aren't about Hydrogen as a transportation fuel or even transporting Hydrogen. They're a mixture of direct on site storage of hydrogen to use as overnight energy when the solar farms no longer work, and largely about ammonia for transport and methanol as a sulfur free marine fuel. Ammonia can be shipped overseas form Australian solar farms using methanol as shipping fuel to supply ammonia as fertilizer and ammonia as a power station input to generate electricity. Dicking about with slippery hydrogen in tens of thousands, hell, millions of small personal transportation pods is a waste of resources and a safety hazard, it's too many individual things to keep maintained to the high degree required to prevent leaks, etc.