The trend lines for social norms (blue) and cultural norms (red) rise together.
“Western” society used to distinguish between good and evil, but that was supplanted by normal/abnormal. Good/evil is a digital distinction with no middle ground, but normal/abnormal produces a continuum. Individuals can be placed on this continuum and subject to some kind of therapy to move them from abnormal to normal. Consider the Autism Spectrum.
This ngram indicates that the word evil starting falling out of favor in about 1842 but has regained some ground since 2000. The recent rise is most likely associated with the discourse on terrorism, particularly after September 11, 2001. Religious discourse in general has increased since about 1980.