Where I live - in a large American city, the biggest barriers to allowing new development are the lack of provisioning for increased density.
Sure, let that new apartment building come up. Screw everyone's commute time, ability to park, availability of services - no, we won't issue enough permits, require the construction come with a massive underground parking facility, ensure there's sufficient expansion of roads, or drastically improve transit.
Improvements have a history of being so slow to appear and in a deficient state, that the prospect of having more people around makes people unhappy.
"The middle class always pays".
