It is a bit of a grey area. They fit some definitions of a cult but not all of them . I consider them a cultish high control group.
“disagree with anything coming from headquarters is a disfellowshipping offense ”
That is technically true but not always the case in practice. If one goes around the Hall deliberately disagreeing,then yes.. In practice many experienced dubs hold personal opinions that disagree with the latest doctrine. The clever thing is who you talk to about it.....