Capacitors are never going to have the volumetric density of chemical batteries. That kind of tech is not going to work for anything that needs to be small and mobile (which includes cars, which need to be small for the amount of energy they can store).

I know less about hydrogen fuel cells, but hydrogen also has very low energy storage capacity per unit volume (unless you can manage to keep it at very high pressure or very low temperature, which introduces its own challenges).

There will be applications that can use these types of things, but I doubt it will ever be a drop in replacement for chemical storage.