One characteristic of large coastal, elite cities, and their international brethren, is high population churn in their gentrified precincts. People are constantly moving out, with new arrivals coming in behind them.
This high turnover has several implications for the churches there. One is that they have to be constantly attracting new members in order to avoid shrinking. Another is that it's very difficult for them to sustain community.
In general, it's more difficult for people to make an sustain long term, deep friendships and personal connections in those cities than it is in most places. They are good places to move for certain kinds of people: the young, people originally from there or from a nearby town, wealthy people, and people with personality types that allow them to live mostly autonomously.
The people in these cities are shallowly rooted, as we saw during the pandemic when large numbers of their most affluent residents abandoned them. This calls into question how real the notion of "in the city for the city" really is.
Escape from New York: https://arpitrage.substack.com/p/escape-from-new-york
Joan Didion's essay "Goodbye to All That" can be found in her book Slouching Toward Bethlehem.