Hydrogen being viable fuel has nothing to do with its production. Its viability comes from high energy density, ability to refuel faster, better performance in the winter compared to EVs, etc. Production, sure, currently it’s fossil fuel based because that’s the cheapest way to produce it. The thing is, it’s not the only way to produce it. There’s electrolysis, then there are bacteria which can produce it, etc. If the demand jumps so will the production and prices will go down. Plus there’s no OPEC controlling prices.
But all of it matters very little. It means you can use fossil fuels to produce greener fuel, and then just switch along the line somewhere. Far easier transition.