Solid Oxide fuel cells run rather hot for a passenger automobile, don’t you think? The beauty of hydrogen fuel cells is that they operate at around 80°C.
Hydrogen fuel cells have thier own problems. Fuel storage being the biggest, Hydration management for the membrane is another stumbling block.
Newer tech has SOFCs running much cooler and more efficient. But it is the heat that allows them to digest fossil fuels and allows the potential of using the current fuel infrastructure.