Darchei Noam, The gedolim disagree. The Chazon Ish referred to NK as “Yidden from before Matan Torah”, meaning their hatred of Zionism was not related to the Torah. The Chazon Ish ZT”L was not a Zionist- witness his whole struggle against mandatory national service for women- but his hatred of Zionism came from a love of Torah, not from a need to vent his hatred. This quote comes from the book “In their shadow” (English translation of “Bemichitzatam” by noted Chareidi askan Shlomo Lorinz). The book brings down a story where a young member of NK accused the Chazon Ish of not being sufficiently anti-Zionist. He also acted with great chutzpah to the Chazon Ish. The young man did not live out the year.
There are similar quotes from The Brisker Rov ZT”L. This is not a knock on Rav Amram Blau ZT”L. But movements tha tuse negative middos by definition draw people with negative middos. The passuk says “Ohavei Hashem sin’u ra”. But some people just need an outlet to vent their hate. Hate without the Ahavas Hashem and Ahavas habrios of the Chazon Ish and Brisker Rav get distorted into sinas yisroel which we see today. Negative middos must be used very carefully and must be matched with constant Torah, Mussar and Ahavas Habrios like the kind done by the Chazon Ish and the Brisker Rav. Negativity breeds negativity.