Convincing modern people that they are sinners is a big problem for Christian apologetics, and has been for many decades.
Moderns are nihilists - they don't believe in the reality of reality - so they believe that sin is relativistic, and can be redefined-away.
Why repent of a sin when that sin can be abolished by a change of law?
Modern people are encouraged by the culture to interpret their feelings of guilt as evidence of oppression - instead of recognizing themselves as sinners, dyed in the wool, they feel themselves to be victims.
No matter what their own faults, no matter what their own imperfections, their bottom-line self-understanding is as a victim.
It is not that they suppose themselves perfect, nor that they are immune from guilt - but that victimhood trumps guilt.
This ultimate, existential self-definition as a victim goes right through modern society, from the most powerful person in the world to the most aggressively parasitic lowlife; and this status pretty much defines the secular-Christian divide.
Self-defined victimhood is at the polar opposite of Christian humility.