I always have felt like blaming cars, of all things, misses the bigger picture.
On the contrary, doing anything other than blaming cars misses the bigger picture that car-dependent development is what drives, directly or indirectly, almost all the pollution except for industry and agriculture:
The emissions of the cars themselves, of course.
The emissions associated with producing all the extra concrete you need to build places to store the cars, as well as wider roads to fit all the traffic. (EDIT: and longer roads, for that matter, because inserting all the space for car storage forces your destinations to be further apart!)
The emissions associated with restrictive low-density zoning codes forcing 90% of the population to live in single-family homes exposed to the environment on all six sides, instead of giving them the freedom to choose to live in denser housing where shared walls increase thermal efficiency.