Anyone who treats science as a religion ends up with a pretty terrifying morality.
Thankfully nowadays even people claiming they do so often actually don't. I.e homosexuality is amoral according to the texts, but society moved on for the most part.
People will at times behave pretty abhorrently.
Stalin wasn't religious, but he still initiated a gigantic slaughter of his own countrymen. Ditto Mao.
Just trying to make the point that being horrible correlates with being human, not being religious.