Moving to better cities does not require intervention. People will do it naturally over time.
In today's world, we see (much smaller) groups of people trying to relocate as their homes become intolerably dangerous. The press calls it "the refugee crisis" and it's causing massive tension all over the world. What do you think will happen if the flow of refugees continues increasing, year after year, for decades?
It’s not a huge deal. It’s a moderate deal.
Moving cities is not a huge deal. I’ve personally done it 3 times. It’s not a small deal either, don’t get me wrong. But it’s not a mayday scenario.
Even my ancestors who made 1/100th the income I do moved multiple times.
And no, it has nothing to do with income