Higher household income doesn't necessarily have to mean higher property prices. It's a factor, but that's only one half of the demand/supply equation. Long term, the price of housing is driven by how much it costs to build more.
Which is somewhat understandable, but there's a balance here between the rights of existing residents vs the property rights of the owner of the property being developed (and future residents thereof). There are also regulatory burdens associated with any legal processes intended to give more rights to existing residents.