Doesn't look like a great path forward - deep internal engine parts need to be modified (no "hydrogen kit" for existing cars), they emit NOx emissions (so not zero-emission), and you have all the disadvantages of a combustion engine.
However, combustion engines have 100 years of development behind them and a proven track record of reliability (probably billions of running hours by now). Fuel cells are still newish - "the devil you know". This would also keep mechanics employed and keep dealership service bays busy... kind of a perverse incentive, but it's there for sure.
It may be a stop-gap, or useful for certain situations (long haul trucking is mentioned). It could be part of the tapestry of technologies needed to move to a more renewable-based future.