Ok. I understand what you mean now, but I disagree on the correlation.
If someone is not religious, they could still be morally advanced. In the modern world people are tending to prefer reason over faith. I would even argue it is way better now that people are directly discussing philosophies rather than following the constructs of religion around it.
If someone is religious in the true sense, their way of life following faith in God also advances them morally. How this works depends on the religion of course. But as I mentioned earlier this tends to create a form of groupism.
So a person being religious or not doesn’t directly mean they are morally advanced or not. I’d say lack of moral advancements are due to other factors, like the evolution of society on top of technology.