Vien is not a Chassidus.
Vien is Chassidish, but it ain’t a “Chassidus”
A Chassidus has Chassidim, in fact it usually has many Chassidim.
However, Vien under the current Rav/Rebbe is bankrupt.
It lost all its Yeshivas/Mesivtas, its Great Shul in Williamsburg is empty, etc, etc,
So, yes Vien is Chassidish, but don’t confuse it with a Chassidus