There has been a longstanding dispute over the viability of building an eruv in New York, both in Manhattan and in Brooklyn. I don't claim to be able to resolve this debate. However, I saw something interesting that I did not know before. It seems that R. Shlomo Zalman Auerbach considered New York, presumably Manhattan, to be a public thoroughfare (reshus ha-rabbim). If so, then he would presumably disapprove of building an eruv in New York.I saw this in an otherwise unrelated comment in Shulchan Shlomo, Shabbos, vol. 1 303:13. I looked through Shemiras Shabbos Ke-Hilkhasah and could not find any similar comments, neither in the name of the author (R. Yehoshua Neuwirth) nor in the name of R. Auerbach. It just brings down the two sides in the footnotes to chapter 17.
Add that to the list of great scholars who opposed eruvin in Manhattan, not that there were/are no great rabbis who approve of them.