I fail to understand how using elemental hydrogen for storing energy has ever sounded like a good idea for anyone.

What sounds like a good idea is using fuel cells instead of ICEs, but using hydrocarbons as fuel, not dihydrogen (also solid carbon is a possible fuel).

The use of hydrocarbons can be carbon-neutral and sustainable, by making them from carbon dioxide and water.

There have been various experiments with fuel cells using other fuels than dihydrogen, but the main roadblocks have been a lower power at a given size than with pure hydrogen and the need for more frequent maintenance, besides the main disadvantage common to all kinds of fuel cells for now, high cost, due to expensive catalysts or to components such as separators that must be replaced frequently.

Nevertheless, we know that it is possible to make cheap and performant fuel cells, as demonstrated by any living being that breathes air.

Hydrogen isn't chosen because it's the optimal technical solution (or even a solution at all). It's purpose is to prevent the transition to BEV technology (as a proposed alternative) and thereby protect the businesses making ICEs. It therefore can serve its purpose even if zero Hydrogen vehicles are made.

Of course this was all for the past 30 years. Since everyone can see with their eyes that BEVs work, Hydrogen's job is over.