

Electricity has been around that long too though, yet there are no serious electric passenger planes (with a decent range)
It has it’s flaws, but it may have a higher ceiling in terms of usefulness. They say they can make it work, which is more than I hear about electric planes for example.
We should be financially encouraging 0 carbon planes, without controlling how, then let the engineers work what tech to do it with.
That requires lots of cropland though. Hydrogen can effectively be made by offshore wind farms etc.
It might work if we reduce standard fuel requirements for cars etc enough.