Exactly.
But they like to debase anything that hasn’t been contaminated yet.
Evil hates good and they can’t stand the condemnation that uncorrupted good makes them feel. So they corrupt it so they don’t feel the guilt and shame that they ought. Then their consciences aren’t bothered any more.
Of course, since God is speaking to everyone (aka “conscience) within the heart, and they can never shut Him up, even if they convert or kill every human on the planet, they will still be tormented with guilt deep inside.