I agree with the principle, but a more detailed look reveals two ways to promote clean molecules.
The first is to support their green potential through subsidies. The lower the molecule's carbon intensity, the more financial support should be available. That support needs to foster the development of an industry. In any case, the scale effect generated by the massive deployment of green hydrogen production should render such support unnecessary. If the size and number of plants increases, costs will go down. It's the same with the development of renewable electricity; cost-effectiveness increases. The economic model could be comparable to that of fossil fuels.
The other way to promote it is to penalize the use of fossil fuels, mainly through a carbon tax or a bonus-malus system, whereby those who use clean fuels are rewarded and those who do not are penalized. The idea is to regulate the market to move towards solutions with the lowest possible carbon intensity.