It is the same reason why we have miles of natural gas pipelines sending NG to local NG turbines instead of a few big NG power plants with wires sending electricity everywhere.
Hydrogen we need to make using a resource intensive process, and it leaks from every single container ever made, because it's literally the smallest molecule in the universe. Hydrogen transport incurs so big losses that it's not feasible at a large scale [0].
To move an equal amount of energy, you need 4x many ships as LNG, because you lose 23% more during transport than LNG AND you need to transport it at -253C which is a whole another issue.
Hydrogen is a good energy storage medium, but it's not practical for transportation. It's a lot easier and cheaper to move the same amount of energy using the power grid.
The future of hydrogen is renewable energy storage, on location. Not transport.
[0] https://vimeo.com/761934482 (16:50 mark)
You do not need 4x as many ships. You just need bigger tanks. Hydrogen is much lighter than LNG. Bigger tanks are not an issue. You're hearing straw-engineer arguments from those with a vested interest to BS about these issues.
Why would the World Hydrogen Congress have a "vested interest to BS"?
The speaker is comparing a LNG ship to a prototype Kawasaki LH2 ship, with actual values for both.
What he's suggesting is that we transport ammonia instead of LH2, ammonia is a lot more stable to transport and can be converted to hydrogen at the destination.
Ammonia is an option too. But this does not preclude other ideas.
We have an electrical power grid, dude. And it works just fine for home BEV charging.