If the clearing rate is equal to the cost of an engineer at a tech firm in SF, the education budget for a small town in Alaska wouldn't afford it.

Your formulation isn't wrong, however it covers only one scenario. What happens when the locality cannot afford the cost to attract people to their region?

This is not even theoretical, its what happened to the rest of the world, as their best and brightest immigrated to America or Europe.

You could say "them's the breaks" and I would understand. However people vote for solutions, so how would you cover the worst case scenario?