No. If you go looking, you will find plenty of counter-examples in History. You just made a statement that the top handful of catastrophic examples were representative of the bunch.
You have massive selection bias in your sample. “Morally-based decision ends well” is not exactly something that makes headlines or that is seized upon by historians to explain memorable cataclysmic events.
You don’t need to be an ethics expert to see a difference between moral principles that lead to suffering, and moral principles that don’t.
Waving away all morality in moral nihilism is teenage-level ethical sophistication.
