To answer the thread title, if nobody can afford the prices, people won't rent and the rents should go down untill they do. That's the theory, in reality it'll propably take an insane amount of homelessness for it to actually turn out that way
I'd like to think this, but this would involve the government converting for profit properties to government-funded enclaves. Essentially, mass section 8 housing. Which a large part of the population would revolt because that's "socialism".
I think the more likelier scenario is companies start buying housing for their employees. Dormitories for the lower end workers, duplexes or single family homes for middle management. Executives will probably still be able to afford housing.
What I find strange about my scenario is, if you're familiar with horseshoe theory, on the ends of the political spectrums; in this case capitalism and socialism; they start to resemble each other.