While you are technically correct, that's not the best model for this. Energy in oil is ultimately stored energy from the sun. But for hydrogen powered cars, we must take one stored form of energy (e.g. fossil, nuclear) and use it to make the hydrogen. Or skip the oil step and use solar.

So question is, are we storing new energy, or converting previously-stored energy to a different format? The latter is an externality as obviously oil, uranium etc were around long before humans.