I’m pretty sure the basic thermodynamics of it are against truly green hydrogen production ever becoming cheaper than the dirty business of producing it by reforming methane from natural gas, unless basically all fossil fuel subsidies are someday cancelled – or else after the energy cost of energy gets so high (in other words, the energy return on energy invested falls so low) that it’s no longer practical to extract fossil fuel from the ground regardless of price or any other economic factor; – but by that point in the future, that same scarcity will have permanently crashed the world economy thus humanity will already be in forced deindustrialization. I could go on…