Things should revert to the mean, but I don't see it happening anytime soon, people come to cities for the opportunity, they stuck in the city due to the property they own and pay off.

They enjoy a certain lifestyle and network effect of education, jobs, transport, finance, and highly dense community and it can be great until it's not, eventually, you reach a point where you oversaturate one place and it begins to decay, homelessness increases and so does crime

I think it reverses in different places for different reasons, some will be due to city decay, some will be new towns/cities starting up offering incentives to move, unlocking of new resources creating new opportunities, people wanting a better deal for their money in terms of property cost, service delivery and influence on a local level