Well here's the awesome thing about geography- there's lots of it.

You don't have to live in a place with a high cost of living.

In most of those places; coastal cities, Chicago, NY; the increase in your wages isn't commensurate with the increased cost of living compared to an emerging city or town. Someone making $80k in Cincinnati lives a lot better than the same person making $120k in Chicago. And that's only if your skills are the type that aren't marketable in towns without a tech sector. Although with emergent decentralized workforces and remote work, even that is becoming less of a factor.

I could do my job from anywhere with a halfway decent ISP, which means I could do it for any company that wanted to hire me and then live more or less wherever I wanted. Why, then, would I choose to pay $2000/mo for a shitty apartment in a major city when I could live like a king somewhere else?