Morality is subjective at the edges. We all share a common morality, otherwise our society would not function. Most of the common morality is captured by laws.

I completely agree with you that law enforcement officers will see it that way. I posit that that is a matter of limited perspective. They see backdoors as a means to catch criminals, and do not consider the implications for surveillance, democracy and freedom at all.

This paper is not aimed at them, it is aimed at the cryptographers, who could hopefully more easily understand that perspective.