Well, it's not.
> AGI smart for some
Of course they will - the population shows a Paretian distribution... In front of trigonometry (or anything), the blind will dismiss as "bullshit" and the half-seeing will call it an "unreachable frontier". But already the right fifth will rank it properly.
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Yes, proper intellect generates ethics ("an" ethical stance, output of the preceding intellectual effort). It requires that adequate level of ability and effort and reflection though to reach specific ethical milestones and adherence.
Unethical behaviour is lack of development. But on the same reasons, the ethical judgement of the assessor may not understand the computations behind instances.
More specifically: how much "reflection" in training and at the instance will have been spent in the conflict between "reaching the goal" and "minimizing collaterals"? It is not granted that the amount of energy spent will be sufficient to reach an optimal judgement.