The issue with ICEs is the fossil fuel part, not the engine part. Synthetic hydrocarbons and alcohols don't contribute to climate change at all. And alcohol fuels are both easy to make and about as good as hydrocarbons.
If you are able to manufacture them in a completely emissionless way. That requires huge energy input though. Certainly has its uses, but too expensive for personal cars I'd think.
What I think would make sense is to use methanol as a seasonal energy store in temperate climates. Manufacture from PV in summer, burn in winter.
It can be scaled up.
Might as well drive a quiet, renewable powered electric vehicle and let the jets use the synth.
Or take the train.