I don’t see how your argument at all follows. Some software projects are impossible without large teams—or at least, impossible to do in any reasonable amount of time. And as the number of people who know a secret increases, it gets harder and harder to keep, not just because of increasing risk of deliberate betrayal, but because of increasing risk that someone will screw up on the procedures for keeping communications between the people involved a secret.
I don’t see how your argument at all follows. Some software projects are impossible without large teams—or at least, impossible to do in any reasonable amount of time. And as the number of people who know a secret increases, it gets harder and harder to keep, not just because of increasing risk of deliberate betrayal, but because of increasing risk that someone will screw up on the procedures for keeping communications between the people involved a secret.