There has been a long-term trend of cities drawing people from the rural areas through economic opportunity. That won’t stop.
Many from the South came for the Welfare benefits and their descendants make up the bulk of the Welfare Class.
Unless the GOP figures out how to handle this situation it is going to be difficult for Republicans in the future.
As you note the cities are critical to the economy and are the economic engines powering whole regions including agriculture.
Civilization itself is a creation of cities which are the places the culture is created.
Democrat controlled cities create economic black holes that suck all the wealth of the city and state. Detroit is the poster child of this but Chicago is going that way and all of California is headed that way. They pay sweetheart pensions and a massive school teachers unions.