Having commercially viable e-Fuels would have a few advantages. You can keep your old car and be net-zero, sport cars would be a thing, you can decarbonize other types of transport which are more complicated to decarbonize than personal vehicles. Like maritime, airplanes, long haul tracking and so on. Its like killing many many birds with one stone.
At the momeny, the fact that ICE cars would be banned could be a red flag for new projects trying to push for e-Fuels as it limits their customer base. This is important because at the beginning they will be more expensive that crude-based products so you need to find a niche market where poeple are willing to pay premium for net-zero. I think that companies like Google, Apple and so on would be willing to pay maybe even 2x or 3x for the fuel if it guarantees true net zero (no offsets).
As for the efficiency. It is true that the e-Fuel based chain would be less efficient than all-electric but there is a way around it. Efficiency is mostly important to keep the costs low. If you need 1kWh on the output and the efficiency is 20% instead of 90%, you will need 5 kWh instead of 1.11 kWh on the input. But what if the input is next to free? Two ways of getting that. One is by having a surplus electricity which we will have a lot as we inevitably have much more installed capacity in solar than peak load. The other one is to build renewables where they work very well (like Mauritania for solar), produce e-Fuels on-site and than ship them globally. Economy of scale will allow you to decrease cost of e-Fuels dramatically.
It might seem like a long shot for you at the moment but I gave it a lot of thought and discussions and research and I think that this very realistic and very likely scenario.
PS: If you want to start a business in this area, let me know. I'd be very interested!