I seriously do not understand anyone in the Bay Area that’s anti development. How can you justify yourself in good conscience to be anti development when CoL is so high?
Of course, increasing housing density highlights other problems: terrible traffic and poor public transportation. We’d need to make large investments in both housing and transportation infrastructure if we’re ever going to make headway in the CoL problem.
So, no. It's normally not a great idea to build a bunch of random housing and hope a total transportation mess--which already describes much of the Bay Area--will hopefully be solved someday.
But a route that nobody uses doesn't have any surplus around which a population would grow.
You can't realistically expect to create substantial residential developments without appropriate infrastructure, and just kind of "fill in the gaps" later – transit infrastructure in particular has long lead times that make that impractical. In reality, planning of residential development and infrastructure changes need to be part of an integrated planning strategy ad the government level.
Paying for infrastructure you can't use just means you're poorer and less able to grow.
But that in itself is a zoning problem. Mixed development that allows the places people want to go to be integrated where people live drastically reduce transportation trips.
Bear in mind too that a fair number of people either can't or won't understand basic economics. I can't tell you how many times I've had or heard conversations that go like this:
Person A: We should kick out all the greedy developers who are raising the price of housing.
Person B: Housing costs are set by supply and demand; if the supply does not increase, prices will rise further.
A: That's not true! When new housing gets built, it's more expensive than existing housing.
B: That might be true of a particular unit, but that's because most people prefer new housing to old housing, and it's extremely hard to construct anything.
A: Just look at that new development: it's more expensive. We need to ban new housing. Plus, I don't want my neighborhood to look like Manhattan.
B: Missing Middle housing will not turn your neighborhood into Manhattan: http://missingmiddlehousing.com/
A: I've lived here for five years and I still don't want to see the neighborhood change.
You can go on for a long time in this vein, with more or less invective.