Michael Liebreich's clean hydrogen ladder is a good reference here:
https://www.linkedin.com/pulse/clean-hydrogen-ladder-v40-mic...It ranks hydrogen use cases by their economic feasibility. The core issue in Japan: they are focusing on things with the least economic potential at the bottom of the ladder and they are doing it with dirty grey hydrogen even.
It's a double fail. Basically they are expending more carbon to magically become cleaner. Which isn't working for obvious reasons and quite obviously so. And then they are using that hydrogen for the least economical use cases. It's not an energy strategy but a let's bail out our car manufacturers strategy.
This article is stating the obvious: this isn't working. Not even a little bit. There's nothing there. Hydrogen cars are a fantasy. Nobody is buying them and even the world's largest hydrogen cheer leader (Toyota) of these things is barely producing and selling any. And as reluctant as they are to produce and sell battery electric vehicles, they still sell more of those than hydrogen cars.
Hydrogen for domestic use also ranks at the bottom in the hydrogen ladder for very good reasons. Yes you can do it. But it's just stupidly inefficient in terms of hydrogen generation and transport losses.
These are not problems you can just wave away with some innovation magic. There is no magical solution just around the corner that will make all of this go away and improve things by 10x. The issues are pretty fundamental and have to do with hydrogen just having a very low energy density by volume (it's the first element in the periodic table), energy conversions having a cost (second law of thermodynamics), and the bonds between hydrogen and carbon or oxygen atoms being very strong.
It takes more energy to break those chemical bonds than you get back in the form of hydrogen. There's a theoretical maximum efficiency to that. Once you have hydrogen, you have to convert it again to do something useful with it. That too has a maximum theoretical efficiency. These inefficiencies multiply. What happens if you multiply two fractions? You get a smaller fraction. Compressing and cooling also takes energy. And if you introduce conversion to ammonia or some other susbtance, that's another conversion, which is lossy. That just multiplies the problem.
So, that means hydrogen should be prioritized for those use cases where you can minimize the losses. Anything involving transporting hydrogen over long distances is a problem. Because of the volumetric density. It's just not very efficient. You need to move a lot of volume of it. And it's a tough substance to contain. Leaky valves, boiling of liquid hydrogen to keep it cool, etc. The losses accumulate rapidly. And even when you contain that, you need to ship about 18x more of it in compressed gas form to match a single tanker of petrol or about 3x in liquid form (cooled to near absolute zero). Compression and cooling take energy btw.
Because of all that, the vast majority of hydrogen produced right now, is produced and consumed on site. Mostly for things at the top of the hydrogen ladder like fertilizer production or use in various chemical processes.