Hydrogen is difficult to store, difficult to transport, low-density (it's the lightest element) and a fundamentally inefficient store of energy. Avoiding releasing carbon during combustion doesn't seem like a particularly worthwhile reason to make all these sacrifices. Carbon release isn't, per se, the problem - it's the open-loop carbon cycle from buried fossil fuels.

I have read that the meme that hydrogen is a good replacement for fossil petroleum mostly gained ground in the GW Bush era, in an attempt to appear to be taking green fuels seriously in a way that was actually friendly to petrochemical industry. It's not a coincidence that 1) Bush pushed the "hydrogen economy", and 2) hydrogen largely comes from fossil fuels.

A really, really good writeup here: https://www.thenewatlantis.com/publications/the-hydrogen-hoa...