Lots of people can't. Most people don't work in tech, and probably can't. Telling service workers to live in the boonies and commute an hour and a half by car to their minimum wage job is stupid and tone deaf, obviously there are better solutions.
>use newly affordable automobiles to get to their workplace
Many metro areas are so congested automobiles are no longer the convenient affordable choice they used to be. For some mass transit is less about being planet-conscious and more about not wanting to sit in traffic for half the day and spend $300/mo on parking.
Property is hardly an optimal free market and there's lots of things we can do to improve the situation other than making fun of "Millennials". Most people I know would happily pay less to live outside of the city so long as they were still well-connected to the city center by the transit network. Expanding and improving commuter rail access and building denser more appealing suburbs will be big wins imo.