in new york you're not remotely right.

the suburbs around new york are some of the richest in the world. Scardsale, every town near the ct border, rye, huge parts of li, montclair nj and the towns around it.

the average household net worth in westchester which is a huge county is $1m, thats on the same tier as wealthy parts of any major city.

Sames true of the suburban sprawl of the bay area and dc.

I'm not sure you're contradicting the parent. There are "elite" suburbs/coastal towns surrounding a lot of "elite" cities. There's something of a preference (and life stage) whether someone has a nice condo in a city or a nice suburban/exurban home (or admittedly both in some cases). The balance doubtless varies depending on the locale; there are some cities that aren't generally considered very desirable while some of thee suburbs/exurbs/nearby smaller cities are.

Net worth means little when you have to spend 2+ hours commuting via public transit 5 out of 7 days per week, so that you basically only live for weekends. Obviously, it's a choice to give up your 30s/40s for a secure 50s/60s or whatever, but the definition of "wealth" is not so clear to me in that scenario.