The thing about the Q Continuum is that they have the ability to resist the death thoughts of each other. Q is a garden-variety deus ex machina with some Greek chorus thrown in. He's more of a narrative instrument than a thought experiment.
I suspect Bixby didn't go there because it's uninteresting. In order to achieve a steady-state "society" you quickly run into ground rules so alien to us that we would not be able to recognize its functioning. When Groupthink reaches the point where the majority can exterminate the minority without effort, you end up with such homogeneity that the only thing left is L'Engle's Camazotz, which is only interesting when the protagonists interact with it as individuals.
I understand why Bixby didn't go there. I understand why L'Engle took the avenue that she did. Literary boredom does not preclude a thing from being. I'm more interested in when the majority can exterminate the majority without effort. Everybody has their finger on the metaphorical button and then has to consciously choose to allow everybody else to continue on.When Groupthink reaches the point where the majority can exterminate the minority without effort,