We pretend to seek out reasons, when we're actually just looking for excuses.

"I didn't actually do anything wrong, something outside of me made me do wrong, you can't prove it wasn't chemicals"

"There's no such thing as a shared moral code ,it doesn't exist, unless someone hurts me and then suddenly, they did something horribly wrong"

Our ancestors are fortunately a bit wiser than we are, they know there are things that cannot be excused, swept under the rug of moral relativism. They can only be "forgiven" as C.S Lewis explains in https://www.cslewisinstitute.org/webfm_send/111

Thinking all there is is moral relativism is a tiny baby step in the long journey of deriving your own objective basis for making moral judgements, and C.S. Lewis's works are essentially religious allegories but with better character development, so hardly a reference that carries rhetorical weight here.

Just as

- there is no conflict between lower level concepts such as quarks, electrons, atoms, molecules and higher level concepts like reactions, processes, yield and throughput

I think there is no conflict between "Genetics, cultural values, chemicals, hormones, electrical impulses" and sin.

I don't expect any answers, but at least I've tried explain my position.