To use Hydrogen for a Jet engine would be uneconomical... unless theres a more efficient way to make it... but AFAIK - Jet engines or turbines work great with slow burning kerosene.
Hydrogen would be better as Rocket Fuel.... well - they are actually used for Rockets... Liquid Hydrogen that is.
As fuel for the normal I.C.E. - well - it does work of course. No doubt about it. But todays research is taking it to a more efficient way of converting power or energy into another form in order to get the most out of its' latent potential. For example, Hydrogen if used in a reverse process of electrolysis - like that of Fuel Cells... it will make electricity and water vapor as it's by products. when it is passed through a membrane with Oxygen.... the catalyzing effect brings Direct Current directly usable for electric motors. This will eliminate the need to carry ultra-heavy batteries. Making Hydrogen is one thing... making the Fuel Cell is another. But it's the over-all interplay that allows a more convenient utilization of power.
Now what does this have to do with the vehicle design? one may ask.... Simple.
The platform used should be manifested outside the skin of the product.
For example... When the T-Rex was undergoing conceptual stages... many ideas were taken into account. Including my old Trima Concept which was made available in public domain in early 2000's.
But the parameters for the design process includes but not limited the following:
It should give a hint that it is still first and foremost a motorcycle.
That's the reason why it has adopted articulated fenders on the two front wheels... and has adopted the cladding of mostly motorbike inspired panels, headlamps and tail lamps and other details akin to Big Bikes.
In the same tradition why the Honda FX Clarity is made so.... it should be able to give a hint that it's a different car. Although limited in design playground, the challenge was taken with enthusiasm.
How honda played it?... they made the bumper Anodized Satin Aluminum Finish - a styling not commonly used anymore specially to combine with the modern shape of the cars where bumpers are integral to the over-all shape. It was - a clever way to do it. Somehow, like adding Parsley to a Dilis or Tuyo Gourmet meal presentation.
The object is to make it stand out as something different. The playing with contrast of color and materials were the focus of this design innovation.