Your numbers are way off. No manufacture would even think about touching hydrogen ICE motors if they only got 10-15% efficiency.

I thought they were using ammonia powered vehicles and calling them hydrogen just because ammonia contains hydrogen. Wasn't there a bunch of hype a few months ago about Toyota inventing an ammonia internal combustion engine that was so efficient it would "make electric cars obsolete"? The article just mentioned liquid hydrogen though. So I don't know what to believe anymore.

I think the biggest thing that people forgot in the efficiency debate is cost. What will hydrogen actually cost to go 100km compared to electricity

and you have to use it up within a week or two, or your fuel disappears

Because Toyota invested a lot into hydrogen instead of EV, and they need to recuperate at least some of it.

While most car companies initially believed liion batteries isnt ready for the market, and wanted to wait for a more safe and dense battery tech to hit market (solid state battery), toyota invested in hydrogen. Then Tesla took the bullet and sort of went against thr grain and created the liion based evs, and the rest of the companies are scrambling to catch up due to the demand for them.

Any push for hydrogen is because toyota invested into it and doesnt want for it to go to waste.

Because some companies just can't get rid of the idea of ICEs. And they don't like that their expertise in making high-quality ICEs doesn't give them much benefit in making electric cars. So they prefer hydrogen to win over electric otherwise they'll have a very hard time competing against newcomers.

In my opinion, it's dinosaurs clinging to their old ways while the asteroid looms large in the sky.

Hydrogen fuel cell vehicles are EVs, have electric motors, and qualify when you talk about "power generation with Hydrogen" and "versatility of electricity". The hydrogen in the tanks is fed into an anode and oxygen into a cathode to power a circuit and drive an electric motor. It's an EV, but the 'battery' is hydrogen. FCEVs could be the key to shoring up a lot of conventional EV shortcomings; lithium-ion waste, electricity grid load, and lifespan, for instance. Combine that with the ICE vehicle in question in the article; Hydrogen ICE engines could provide routes for retrofitting existing combustion vehicles, adding additional demand to improve supply infrastructure and improve green hydrogen supply. These are well-warranted experiments for Toyota to be undertaking on the global stage; as crucial as any EV battery investigation!