Comment by antonvs
A big part of the problem here is that this conspiracy theory plays right into what its followers want to believe anyway: their idea of an ideal city is one where you can easily get anywhere by car, and there are lots of highways, strips, other roads, and plenty of parking.
It's what they're familiar with, and any suggestion that it could be improved by catering less strongly to individual vehicles and with a stronger emphasis on public transport, bicycles, walking etc. is automatically resisted. The conspiracy theory fits this bias perfectly.
It's not so much that they have "opposition to livable cities," it's that they have different beliefs about what's livable.
The point Strong Towns is making is that whatever you believe, you can’t live outside your means forever. The bill for all that infrastructure will come due, taxes will go up, people who still can will move away, and the town will start falling apart.