You are being very reductive and writing out entire categories of reasons why housing is unsustainably expensive. In your next two sentences:
> People are forced by market forces to move into ever denser cities.
Lots of us already live in cities but our neighbors and elected leaders have let this get massively out of hand. I have lived in Seattle my entire life, as has my wife, and we raised kids here. One of them has had to move away because they can't afford housing here and the other has moved to Marysville just to be able to afford something.
My wife and I are both getting older and didn't want to climb stairs to be able to get to our front door (Seattle, as you may recall, has a lot of hills). Even though we had nominal equity in our house, the red hot housing market here means that equity didn't go as far because we wanted to stay in the same region to be near family and friends we've had our entire life.
Never mind that a lot of those "trendy" areas are where jobs and cultural activities are. Housing is "cheap" in the US if you follow the "just live in the middle of nowhere" model, which of course lots of people don't want or are unable to do.