It's artificially cheap to live in cities because their daytime populations are not all competing for beds close to downtown. If residents of downtown condos had to pay the true cost of sharing minuscule housing stock with an entire city's worth of labor force, we'd have a lot fewer middle class people living in cities than we already do.
I'm sensing an implicit assumption that cutting out driving would result in building more density. But suburban commuters don't write land use policy for urban cores - their existing residents do, and they don't want it, because of noise, shadow, undesireables, etc. They already don't need to drive. Turning the screws on suburban commuters won't change urban NIMBYs minds on what they want their neighborhoods to look like.
I'm sensing an implicit assumption that cutting out driving would result in building more density. But suburban commuters don't write land use policy for urban cores - their existing residents do, and they don't want it, because of noise, shadow, undesireables, etc. They already don't need to drive. Turning the screws on suburban commuters won't change urban NIMBYs minds on what they want their neighborhoods to look like.