Jobs weren't "concentrated" per se by any form of planning or centralized action, employers simply shifted to urban centers because the amount of skilled workers and other necessities (such as high speed Internet, universities, road and rail infrastructure) was vastly higher there than in dilapidated flyover-state villages. Additionally, rural areas got devastated by mechanization of agriculture following WW2 and later-on the closure of manufacturing plants and the mining industries [1], which led to a massive rural flight movement as everyone who could fled to the only place where employment was available - urban areas.
The fix to the housing crisis would be to invest in rural areas again - there is no limitation in the nature of the work at all that stuff like a callcenter or a bunch of programmers can't work from some rural town, but as long as there is no actual high speed Internet or no amenities (healthcare, education institutions for children, entertainment) worth their name employers won't establish shop there and employees won't move there. Would you, even for free rent, move to some small town where your children have no perspective?
[1] https://www.theatlantic.com/business/archive/2012/01/where-d...
