Do you remember that evil conquering species of aliens from Star Trek called the Borg? Their lack of individualization and their collective function gave them an edge over the rest of the species in the galaxy: no emotions, no opinions, no disagreements, no objections. Basically, no life.
The reason they were so popular in the sci-fi universe was because they were so realistic they eerily remind us of collective groups of actual people living on this planet. Such people, who lack conviction in themselves and generally possess lower emotional and technical intelligence, tend to form uniform groups in which their beliefs and actions are dictated to them. They consider all others to be their enemy and they need to assimilate as many as possible as validation for their poor substitute for true conviction. They are so eager and willing and ready to worship an icon who represents their group’s identity, which they so badly need (lack). They are aggressive due to the cognitive dissonance resulting from a subconscious conflict of reality and compulsive faith in obvious lies.
in essence, they end up behaving like a bunch of fish, all following each other without knowing who they’re following or why.
Unfortunately, they tend to multiply rapidly and cause damage. Inevitably, though, sooner or later such groups end, because they can never match the intellect and emotional strength of a self-realized individual, despite their numbers.
Not only religions are categorized as such. Political ideologies, nationalities, “races”, sports teams, rock bands, anything that forces team members to lose their individuality in a us-against-them mentality is just as detrimental.
The tragic majority of humans, for all their mental potential, still remain sheep.