Golfer, your #1 tragedy, is the same as that of the OP.
I believe TruthWins’ point is, that because there are so many Yidden concentrated together in one area they have divided into factions, and many may consider themselves better than others or at least have reason to separate themselves.
Consider this: I remember hearing an interview with the late Chazan/singer Reb David Werdyger z”l. He was asked, as a Gerrer chasid, how was it that you sang nigunim of Belz, Chabad, Modzhitz, etc (or whatever it was). His answer was most enlightening. After the war, there were Shomrei Shabbos and non-Shomrei Shabbos. No one cared what kappel, hat, streimel or spodek you wore. You were happy to see a Yid who still believes ‘az s’iz dor a bashefer in d’velt’ (that there is a Creator in the world). There wasn’t a difference between Gerrer nigunim or Modzhitzer nigunim etc. any more than there is a difference between singing Shabbos nigunim or Yomtov nigunim. Nowadays, our strength is that each group has grown, and has set themselves up as an entity of its own. That does not encourage achdus, it only makes it more difficult.
Another point: By way of example; In Antwerp, there is one Vizhnitzer Beis Hamedrash for the chassidim of 4 different Vizhnitzer Rebbes. (2 in Bnei Brak, 1 in Monsey and Seret in Haifa). There are so few chassidim of each Rebbe, that they have never split up, and all daven together, ‘praver’ together, and differences are hardly noticed. In big cities, like Yerushalayim, Bnei Braq, Boro Park etc, I’m sure each one of these groups has their own Shul, and possibly schools, yeshivos, kollelim etc. Where do you think there is more achdus?
In a small town, there will be maybe two shuls, (you can’t just have ONE shul ;)), and many more different types will daven together, get to know each other, overcome each others’ differences and, thereby, bring more nachas ruach to the Ribono shel Olam, the Father of ALL yieden. This will bring Moshiach, and ultimately the return of the Avodas Beis Hamikdosh.