Reject the premise. Ethics evolved through natural & group selection which suggests they are consequentialist at root. 

Society is a complex system in a complex environment, so consequentialism is impossible to enact in practice. Deontologic rules developed to codify best practices; bit those best practices become pathological if conditions change.

So then character variance serves the role of recombination and mutation so the evolving system can react to changes in technology and environment. Even character traits like psychopathy are valuable and celebrated in society in certain situations.