Sefardim were named after Sefard or Spain and Ashkenazim after Ashkenaz or Germany, yet today there are virtually no Sefardim in Sefard or Ashkenazim in Ashkenaz. The old Chassidic communities of Eastern Europe and Russia are long since smashed to bits, the Jewish communities of Western Europe increasingly succumb to assimilation and the Jews of the middle east have for the most part left their lands.
The old Jewish communities, the traditional places where Jews once lived have been for the most part destroyed or wither away. The geographical distinctions collapse as most Jews increasingly live in two new countries; America and Israel, and in communities where they are fairly close together. No longer do countries divide minchagim but often miles or a handful of blocks or nothing at all. The old separatism is gone along with the old communities but the customs and traditions of those communities remain and continue on. To most people a black hat is a black hat, but to those who notice can see the vast differences in headgear even among this Chassidish\Litvish headgear from wide brims, tapered brims, felt, etc... And those differences neither begin nor end with black hats.
To a casual observer one group of Jews praying is much like another. Heads bow, words are said and recited from prayerbooks. Yet those who know can see the many variations. Nusach Ashkenaz and Nusach Sefard, which is really the Nusach of the Arizal adapted from the prayerbooks of Portugese Jews and Nusach Ari, which is really Lubavitch and the actual Nusach Sefard of the Sefardim. The differences are not objectively too staggering but each man clings to his particular nusach, to the nusach of his father.
Are those differences really needed? Do they divide us and keep us apart?
Certainly some do. When someone will not consider a chassan or kallah from because of such differences, minchag begins to obstruct the perpetuation and life of the Jewish people. One wonders how much of the so-called 'Shidduch Crisis' would even exist if the barriers between misnagdim and chassidim, ashkenazim and sefardim, haredim and dati leumi were dismantled.
Yet at the same time to return to that group of Jews praying, there are many minyanim when you can see a forest of black hats and kippa srugot, black jackets and blue jeans and those differences seem very minor after all. And when Kaddish is said and everyone responds, amen. The Chassidim may respond, Omeyun and the Litvish, Omein and the Israelis, Amen and yet they are all saying the same thing regardless of accent, affirming the truth of our G-d, the G-d of our people Israel.