In the time after Shabtai Tzvi (someone who tried abolishing the torah and its mitzvos, so please don't make idiotic comparisons), Jewry was in a funk. There were the great learners, but most Jews were very simple, unlearned, and considered to be totally worthless by the learning class.
The chiddush of chassidus was that every single Jew is precious and loved by Hashem as a diamond, something that had been completely forgotten from the time of the rashbi until the middle ages.
The Chasidic way taught the value of the tehilim of a simple jew was as valuable to hashem as the learning of a gaon.
That teshuva didn't have to come from fear of Gd and Hell but from love of Gd.
That what we do shouldn't just be for Gan Eden and personal reward, but out of pure love for hashem and wanting to do what He wants.
This eventually led to the Lubavitch mivtzoim movement which caused such hatred of chabad that hadn't been seen in some time. At least until the "velt" saw how successful it was and wanted it for their own. And yes, many other Chasidic philosophies became a part of litvisher thinking as well.
There is no wrong way to serve hashem as long as you're following shulchan aruch, though that's not to say we don't have what to learn from each other.
But these witch hunts and unsubstantiated sinas chinum are the same thing that destroyed the 2nd temple. This hate of lubavitchers, even if it's only externally displayed in a joking manner, among the litvisher velt needs to end already.
Surely if Jews would just get along we would merit to be reunited with a 3rd temple. And yes, that will be together with whatever leader Gd decides is the right one. If Gd picks one and it's proved beyond a shadow of a doubt somehow I think we'll all manage to accept His decision
L'chaim.
