Public transit won't reduce the cost of housing in cities. The opposite has been shown. Zoning protects incumbents -- always. Incumbents are the reason more

Public transit won't reduce the cost of housing in cities. The opposite has been shown. Zoning protects incumbents -- always. Incumbents are the reason more density is not being built in places like SF. Every solution you've presented has been done, is being done, and will always be done until it becomes politically unpopular to do so. I don't see how doing it again will solve anything.