The cult and anti cult movement in the USA have had a history of bouncing back and forth. I wish I had time to go into this in more detail. Obliviously the period from 1946 -1965 was quiet in this regard. But at the peak of the counter culture movement from 1965 until 1969, the cults had enormous success. But it did not end there. A California judge decided in one case that there was no such thing as "brain washing". That was under the influence of the mad professors of sociology that received enormous sums of money for their "expert" testimony that gave clean bills of health to cults. The 1980's saw a rise in the anti-cult movements but the anti cult movement was brought to a dramatic finish in 1990.
In any case the signature of the Gra on the Cherem [excommunication] had a similar history. It was meant to be the opening salvo against the cults. But the lukewarm reception of his opinion doomed it to oblivion. Still when the Litvak yeshivas arose and after that the Musar movement, there was some attempt to distance themselves from the cults with little success. Thus most people that saw through the charade of the cults simply wanted nothing to do with Torah at all since the Sitra Achra [Dark Side] had become so tightly bound up with it.
In any case the signature of the Gra on the Cherem [excommunication] had a similar history. It was meant to be the opening salvo against the cults. But the lukewarm reception of his opinion doomed it to oblivion. Still when the Litvak yeshivas arose and after that the Musar movement, there was some attempt to distance themselves from the cults with little success. Thus most people that saw through the charade of the cults simply wanted nothing to do with Torah at all since the Sitra Achra [Dark Side] had become so tightly bound up with it.