Necessary but not sufficient is really tough for some people isn't it?

Possibly Its turning you car into a more efficient gasoline-powered vehicle.
Electric engines are efficient. Internal combustion engines less so.
So the combination of an efficient fuel cell and electric engine *may* outperform an ICE car.
Also you can still use batteries for short trips if it is a plug-in which is the dominant use case.

The other advantage of using a fuel cell is that it makes it feasible to capture the CO2. In an ICE because you burn the fuel the concentration of CO2 in the exhaust is low, making it impracticable/expensive to capture the CO2.
It may be possible then that when you are filling up to return the CO2, which can then be used to produce a synthetic hydrocarbon based fuel.
Major technology hurdles, but a possible route to solve both the range problem of electric vehicles and the emission problems associated with hydrocarbon fuels.