The Zeta are accused of having a group mind, seemingly operating like insects, by rote, and without individuality. Where did these assumptions come from? First, we reproduce by cloning, so our appearance can be remarkably similar. Second, our mode of communicating is telepathic, over the heads of humans who for the most part sense no conversation going on at all. Third, there is a lack of argument and indecision that humans see in us when we are at work attending to our contactees, as we have all agreed ahead of time on how to handle issues that might arise. Humans who see us having a group mind are drawing these conclusions on scanty data.
Imagine how adult male humans would appear to an alien race encountering them only at work. There they all are in their standard dark gray business suits, white shirts, and ties. Similar hair cuts. Beard shaved off. Carrying identical black briefcases. Greeting each other with the standard hand shake. Clearly, this is a group mind. When the leader speaks, the others all nod and smile slightly. They even clap as a group! The data missing from this picture distorts it. What the alien has not seen is the gripe session over beer after work, the thoughts running through those seemingly compliant minds, the wide range of recreational and sexual interests engaged in over the weekend, the preferences expressed at lunch as the group argues over what restaurant to go to, and the wild bikini shorts one of their number may be wearing even while at work, fitting in.