Perhaps groupthink works.
M-W:
groupthink: a pattern of thought characterized by self-deception, forced manufacture of consent, and conformity to group values and ethics
The first paragraph from Wikipedia on groupthink:
Groupthink is a psychological phenomenon that occurs within a group of people in which the desire for harmony or conformity in the group results in an irrational or dysfunctional decision-making outcome. Group members try to minimize conflict and reach a consensus decision without critical evaluation of alternative viewpoints by actively suppressing dissenting viewpoints, and by isolating themselves from outside influences.