This is a tricky subject. Most fuels require a certain amount of processing to be ready for use. Fossil needs refining, H2 needs extracting and transporting, even electricity needs to be generated (try saying it’s greener when the grid for some countries is still mostly fossil powered).
I did an interesting read recently on another thread an the greenness of EV’s here:
So, if E fuels can be produced cleanly then I can’t see a reason why that shouldn’t be allowed, at least to keep the classics running
It would be nice to see classic cars able to run on some form of E fuel, though I hold my doubts this will be the case. Many were made to run on the old leaded fuel and needed the timing retarded when unleaded became the norm and E10 proved to be problematic for older cars let alone classic ones and I think E fuels will be a step to far especially in the classic category. I also believe if E fuels do become available it will be for the latest cars if not a new generation of the ICE.