This is one of those cars that's interesting to me, but I don't know that we'll ever go this route in a significant amount. Problem is how complex it is to create hydrogen, although 'green hydrogen' is a thing, it would take quite a bit regardless. Interesting to note that if we could extract only 2% of the hydrogen burried under the earth, we could power the entire world for over 200 years. Which is crazy to think about.
The other interesting thing about these cars is the output is water out of the tailpipe.