I live in San Francisco, lived in Chicago proper for about 10 years, and hail from Detroit (yes, actual Detroit). The Bay Area is exceptionally inflated right now (which soon will correct itself somewhat, I think -- it's beginning to), but here's the thing: I was always able to find reasonable rent, in cities, living in alleged "so-so neighborhoods" that actually weren't -- they were awesome, they just weren't hip. I was always near public transportation, had all the amenities, etc. Sometimes my train ride was a little longer, but so what? And my salaries were always significantly higher, so honestly, it all seemed to net out: housing cost a little more, but I got paid a lot more, so there was that. I realize not everyone is this lucky; you can get paid crap and live in a costly place, certainly.
I have NYC friends who live in awesome parts of Queens and Astoria, and know two who bought condos in the latter for < $200k several years ago. Very reasonable for NYC. No, it's not Manhattan, but they're not struggling and they're not paying 50% in rent. I have plenty of friends who live on Staten Island and it's LOVELY -- green, quiet, and a FERRY commute!
As for the Bay Area, I sincerely do not know why people are obsessed with staying in San Francisco. Sure, it's fine, I live here, but there are SO many lovely places to live and it's so easy to get around via public transit. I couldn't live in all the Bay Area towns that I'd want to in a lifetime. Live in Vallejo and take the ferry, for example. There are tons of places to live in Oakland -- which is a BIG city -- that are near transit.
Five and six years ago -- before our rental market really exploded and housing prices were down due to the crash -- I had one conversation after another about "Now's the time to buy" with people who had the downpayment and made lots of money (yes, I realize this is not true for everyone). "Oh, but I have rent control," they said. "But you should secure your housing while it's less expensive, if you want to stay here," said I. And now the landlords want them out, are selling the building, what have you. I think a lot of people just do not think longer term, or what might happen when things change.
I do believe the folks who say they couldn't get jobs in some parts of the Midwest (or that those jobs don't pay enough to do things like repay student loans). It's why I moved. I also love living in real cities and I HATE DRIVING, so I need to live in a place with rich regional public transit that is bike friendly. I couldn't stand southeast MI or northeast OH, so I left... but by just exploring slightly different areas, I could always live fairly affordably and fairly centrally.