[Zathras]

Actually there are two major problems.
Extracting H2 costs energy and costs more than you get out.
H2 molecules are so small that Hydrogen leaks are almost impossible to avoid.
Other than that, it works fine

[dhs12345]

And it seems like H2 would be more volatile than gasoline since it is a gas at room temperature and would be under pressure in whatever storage container is used.

It if the container were ruptured, the gas would quickly disperse within the air and, if a ignition source is available, would more likely ignite all of the fuel instantly.

FAE bombs function the same way.

Not so with a gasoline in a gas tank. Actually, gasoline has to be atomized in order to burn properly.