The Rebbe thanks the author for Fargangene Velten, appreciating its warmth but warns against portraying Chassidic life as a thing of the past. He emphasizes that Chassidus is eternal, and even if times are challenging, we have the strength to bring more light and prepare the world for Mashiach through spreading its teachings.
https://www.torahrecordings.com/rebbe/004_igros_kodesh/iyar/1009