I met my wife on the UWS, in my early 30's. In my experience, most of the singles on the UWS do eventually get married and most of those within their childbearing years.
There seems to be a tendency for the Yeshivish and Centrist Orthodox communities to lament the "shidduch crisis" among their 20-something children who worry about the color of a boy's shirt or where their parents went to camp. Then those communities turn around and suddenly blame it all on the singles culture of the UWS.
The UWS singles have the healthiest attitudes I know in the Orthodox community. They don't reject potential spouses for nonsensical reasons like family backgrounds and they're not focused on having a boy sit in kollel instead of supporting his family. They don't care if the potential spouse's parents are rich and they don't date when they are far too immature for it. However, all of those things ARE practiced by the dating culture of Flatbush, Passaic, and Lakewood.
So if people choose to stay single longer on the Upper West Side, at least they're not spending time in some bizarrely artificial dating environment and at least they're not being pressured to make bad decisions by parents and mentors who are worried about "keeping up with the Goldbergs."
Instead of feeling lonely and isolated for many years in a community where they are an object of pity and subtle disrespect, thank G-d that UWS singles have the opportunity of participating in a culture that values them as mature adults and gives them a sense of community and belonging.
The Orthodox singles of the Upper West Side have high shul attendance, sit on the boards of those shuls, invite each other to beautiful Shabbat meals where the zmirot go on and on, and go to Torah classes in huge numbers. They have very rich Jewish lives, far more so in my opinion than 24 year old women who live in their parents’ houses and panic because they’re not yet married.
There may indeed be a "shidduch crisis" of sorts, but is entirely artificial and it has nothing to do with the Upper West Side. Rather it is the skewed mentality in Centrist and Yeshivish Orthodox circles of pushing 22 year olds to get married while at the same time putting artificial unethical and un-Torah barriers in their paths to do so.
I admit, it is sad that some older Orthodox singles on the Upper West Side have not yet met the right person to marry when they’ve reached their forties. But the system there is still FAR healthier than the warped sensibilities of Flatbush.