The pool of qualified software engineers outside of high-cost urban areas is pretty shallow. I run a 100% remote company in the midst of staffing up. We're looking for database internals people. There are not a lot of qualified candidates in, say, Oklahoma.

If COVID-19 really helped people to work from the Ouachitas at reasonable salaries, it would be completely awesome. But we're a long way from that. I love remote work and would like to see more people do it. But the past history of epidemics (e.g., 1918, the 1665 London plague, etc.) indicates people will go back to previous behavior--favoring urban areas--once the crisis passes.