At first glance, he has a point. The median price of a house in Banning, California (which I think counts as the fringe), is $257,000, which seems pretty affordable. Here is where Banning is:
There is not a lot of, um, public transit available in Banning. The nearest job centers are in Riverside and Palm Springs, which are 31 and 23 miles away. Riverside has about 170,000 jobs; Palm Springs has about 26,000 jobs. So let's say average distance to jobs is about 30 miles.
What are the implications of this for affordability? First, the cost of driving is, according to the Federal Government, about 58 cents per mile. This means driving cost is about $35 per day. Let's say people can work from home one day a week, so they drive to work 16 days per month. Living in Banning adds $560 per month relative to living next to a job.
Now let's say you're a parent and need to pay for daycare. As best as I can tell searching daycare websites, the least expensive late afternoon care costs about $8 per hour (feel free to correct me if I have this wrong). Assuming an afternoon drive of 45 minutes to Banning, that is another $128 per month per kid.
We have now added $688 per month for a household with one young child in living costs by living at the fringe. At a 4 percent interest rate, this "payment" translates into a $144,000 mortgage--that $260k house is similar in cost to a $400K house near jobs.
Note I haven't taken into account the opportunity cost of time, and I am only talking abou private costs. Surely there are social costs to having people drive longer distances--particularly with respect to greenhouse gas emissions.