Atheists are more likely to be left handed, study findsReligiosity is a characteristic which has been shown to have a genetic component. Like left-handedness, deviation from religiosity might be a genetic deviation, or mutation. The significance of mutations in modern societies is modeled in the "Mouse Utopia" experiment:
Mouse Utopia and its Human ImplicationsMice living indulgently in a utopian environment fail to cull weaknesses that appear in the genome. In the real world, weaker mice would be removed by predation. In the mouse utopia they perpetuate the genetic mutations until the entire population can no longer self-sustain.
The implication for humans is the same. Medication and preservation of the weakest also propagates through the human population as significant portions are no longer stressed into early demise. The generational effect within Britain is shown in the article linked.
The connection to Atheism and to Leftism becomes obvious, as AtheoLeftism fights for "free stuff" and "increased access for less qualified individuals", and use fictitious offenses to command power to themselves for no productive reason.
I suspect that the degradational affect on the amygdala in the brain is part of this mutational issue:
The Evolutionary Psychology Behind Politics: How Conservatism and Liberalism Evolved Within Humans, Third Edition