Unfortunately, hydrogen is just fundamentally not as compelling. Fundamentally much less efficient (round-trip), volumetric energy density basically identical with state of the art batteries (which are improving), much more complexity, greater safety concerns (really high pressure plus the most flammable gas there is), material constraints... You still need a lithium battery. You cannot charge at home. The fueling infrastructure is more expensive than gasoline pumps or electric charging stations (and sometimes not even faster than Tesla's 250kW v3 charging... i.e. if you have two cars fueling, often the second car takes much longer as the station's buffer tank is emptied... to get the 5 minute fueling speeds, the hydrogen must be compressed to extremely high pressure... 5000psi... and cooled to cryogenic temperatures otherwise it will heat up the existing hydrogen gas inside the car's tank). The fuel is more expensive than gasoline.

In fact, a high end long range Model 3 has more range (322miles) than the Toyota Mirai (312mi) but costs less ($49k vs $59k). Is dramatically faster (4.4 seconds 0-60mph vs 9 seconds). Also has vastly greater number of charging stations (and can slow charge from any 120V outlet).

Fuel cells themselves are expensive. Estimates are about $11,000 or so for the Mirai fuel cell stack (not counting the secondary systems like the lithium battery or even the hydrogen tank), or about the same as what the 75kWh Tesla Model 3 Long Range's pack which has greater range. So fuel cell cars will be fundamentally more expensive up front, more expensive to run, more maintenance, with less convenient charging.

To me, a plug-in hybrid (even if using synthesized carbon-neutral hydrocarbon fuel) is much more compelling if you wanted a technological alternative to pure electric. You're not going to be stranded due to lack of charging infrastructure, can charge at home, don't require super high pressure tanks, can fuel fast, etc. At least they have that going with the plug-in version of the Prius.

But hydrogen just doesn't make sense for cars. Maybe on very large vehicles (ships, maybe airplanes) that can use liquid hydrogen (much denser than compressed hydrogen and doesn't require ultra-heavy high pressure tanks).