> But I'm skeptical that increasing building or density would actually lower housing costs. If that were true, high dense cities like Beijing, Tokyo, Singapore, or Hong Kong would have much lower cost housing.

Increasing building and increasing density are different things. Singapore and Hong Kong are dense because they have a very limited geographic area to build in. You can’t point to their density and conclude that adding housing doesn’t help lower housing costs. They would be even more expensive if they weren’t so dense.