When a company publicly proclaims "omg, unchecked development will lead to AI destroying humanity!" (or similar), how brave/stupid would an employee have to be to go against the grain & *publicly* proclaim an opposing viewpoint?

Chances are their paycheck requires enough bravery/stupidity that few (if any) dare to deviate from company groupthink too much.

Employee accepts & lives by that long enough, and they might as well be part of a religious cult.

That religious angle could be just similarities in the psychology / group dynamics involved. Same mechanics -> same patterns observed.