No, it can lead to a protected bubble of indoctrination and propaganda spreading efficiently without any countering - which then spreads into the real-world, wh

No, it can lead to a protected bubble of indoctrination and propaganda spreading efficiently without any countering - which then spreads into the real-world, where real clashes and violence is materialized. Even if the populations were on both or could both move to their own isolated islands, eventually a bad actor is likely to try to take control for their own benefit (and then perpetuated, whether by something like a military-industrial complex, or other); and when land isn't an issue then populations can stay separate enough, however yeah, someone always seems to want more and invade, and so at minimum you have to plan to protect against such potential threats - and without using fear tactics to control or manipulate a population.