There are certainly hot spots in places like NY and SF, but it's not just one area. Lots of cities are growing. And it's not all due to evil corporations running amok, at a certain level it's just capitalism itself that requires growth - the GDP has to keep growing year over year, and the population probably has to grow slightly to provide for that growth. Immigrants move in, and children grow up and need somewhere to live. Add in the generational effect of baby boomers, i.e. that older people retiring and staying in their homes mean that we need more housing for the same number of jobs.
Specific booms like tech in SF may exacerbate the problem even more, but fundamentally our way of life just requires continual growth. This is at odds with the NIMBY attitude that I have a right for not just my home, but every building in my neighborhood, to stay exactly the same as the day I moved in. It's not at odds with affordable market rate housing, that just requires supply keeping up with demand.