>>510294669 (OP)the ancient city state practiced dominion over the nearby agricultural lands. the city offered protection and the adjacent country gave food.
what does a city offer these days to justify its dominion over the country and secure its food supply?
objectively modern cities are rich, yes; but rural areas are more self sustaining than ever before. manufacturing happens in outlying areas, and increasingly in the middle of nowhere.
I see a different future, OP. making complicated manufactured goods no longer requires a city. the city may come to be dominated by the surrounding country in time. cities like detroit will be lost. paris and london will be circumvallated, forgotten, soon to be unsanitary and starving unless they pay significant tribute to the country. this is inevitable as automation and machine learning replace the need to gather millions of workers in one place, simplifying logistics and making it trivial for a rural settlement to or single homestead to get all the manufactured goods it needs.