but that's not the case here
But this is in fact how the police argues. Climate protests are terror attacks (since they disrupt traffic) and therefore this is justified.
Pretty sure the Bundesverfassungsgericht (basically our supreme court) will shut this practice down – just like all the other times Bavarian laws have been ruled unconstitutional – but Bavaria doesn't care. They scrap the law and replace it with a similar unconstitutional version and wait 2 years until the Bundesverfassungsgericht rules it unconstitutional and so on.
You got any idea of the energy density of Hydrogen? On a per m3 basis, batteries hold a lot more energy.
BTW, hydrogen doesn't get burned.