>>2013532>new space on the road is filled up so quickly because so many cars are single occupancyHighways don't "fill up" unless there's people around it, and any example of "induced demand" is more population growth. If you were to simplify it, it would be a positive ratio of highway construction and population growth, because as population grows you need to add appropriate infrastructure.
For some reason, this has been oversimplified to "if you add highway lanes/new freeways cars will just materialize" regardless of other infrastructure, population growth, and so on. Even when Francesco Redi proved that flies do not spontaneously generate from rotting meat, there must have been midwits for years that claimed the opposite.