> As for "lie-cheat-steal machines", I've personally observed it across thousands of children. It mainly happens at 11-13 years of age, middle school in the USA.

Nonesense. First, you did not personally observed thousands of 11-13 years old.

Second, 11-13 years are pretty empathetic and already have a lot of values in them. They do lie, just like most adults do, but they don't steal and don't cheat all that much. They are already building pretty nuanced value system.