Sounds like a petrified civilization.
In the later Dune books, the protagonist's solution to this risk was to scatter humanity faster than any global (galactic) dictatorship could take hold. Maybe any consistent order should be considered bad?
Most people's only exposure to claims of objective morals are through divine command so it's understandable. The core of morality has to be the same as philosophy, what is true, what is real, what are we? Then can you generate any shoulds? Qualified based on entity type or not, modal or not.
But I'm just not sure they are in the same category. I have yet to see a convincing framework that can prove one moral code being better than another, and it seems like such a framework would itself be the moral code, so just trying to justify faith in itself. How does one avoid that sort of self-justifying regression?
Faith in itself would be terrible, I can see no path where metaphysics binds machines. The chain of reasoning must be airtight and not grounded in itself.
Empiricism and naturalism only, you must have an ethic that can be argued against speculatively but can't be rejected without counter empirical evidence and asymmetrical defeaters.
Those are the requirements I think, not all of them but the core of it.