(...)because $24k is hardly unaffordable.
It's not unaffordable. It's uncompetitive. A Dacia Sandero costs $9k, runs on LPG, transports 4 plus luggage. $16k covers a lot of cost for the fuel price difference, and you get a lot more use cases out of the vehicle.
The Lit C-1 doesn't compete head-to-head with cheap cars, like the Dacia Sandero. Yes, the Sandero has all of those advantages over the C-1, but cars like that are much more expensive to own in the longer term, will never be as environmentally friendly, are less agile in traffic, probably less fun to drive and certainly don't look as nice. Those are also the reasons (in descending order) that I would have for buying a C-1.
Perhaps I should also mention that I live in the Netherlands where the gas price is currently about $9.00 a gallon (the highest in the world, mostly due to excise tax) and commuters tend to spend a lot of their time stuck in traffic -- another reason why I find the C-1 so appealing. Also, the Dutch government has extra taxes for people with cars than run on diesel and LPG, so cars that burn those fuels only makes sense for people who expect high mileage.