If you compare the range of a 25 year old EV with a new one, it's pretty obvious that technological advances played as much a role as "environmentalism." California wanted to phase out gas after the smog nightmare of the 80s, saw the cars got <100mile range, couldn't do it. Only now is it potentially practical.

Hydrogen has a ton of shortcomings still. Technology might improve some of those too, sure. But if 75%, say, of the most severe environmental impacts of cars are mitigated by EVs, leaving a much smaller-sized problem in their wake, the technological advancements will have to be proportionally even stronger and easier to overcome to make the market move on again. (Or if EVs never replace >80% of new gas vehicles or so... but if inertia against change is that strong, that's not a benefit for hydrogen advocates.)