Smaller batteries, faster cars. In Germany one can really use all the available power in stark contrast to neighboring countries. Lighter cars and fast refueling for long distance travelling are very beneficial, not only to Germany.
Hydrogen sounds useful for commercial vehicles where you can plan routes and stay close to pumps (eg. delivery, bus, etc.) Sounds horrible for personal vehicles.
I can see Japan investing in it - you are unlikely to travel out of country with your car.
On the other hand, if hydrogen proves to be a lot more expensive than a BEV, then you expect fewer hydrogen refueling stations, which makes hydrogen less attractive.