I would say that the more secular countries of the world tend to have lower crime rates and that the prison population of secular persons tends to be under represented. Now does this prove that atheists are “better” of course not.
However it does show that morality is not tightly coupled to ones religious belief, and to be honest I am very happy that is is not.
I find the writings of the Abrahamic religions repugnant and the god Yahweh is typically less moral then those he is directing his wrath towards.
Some who are non-Christians as myself also find the concept of vicarious redemption and the celebration of human sacrifice through ritualized cannibalism morally repugnant.
Most biblical laws I find completely repugnant, from stoning a non-virgin to death if she is discovered on her wedding night to selling a raped virgin to the rapist and forcing them to marriage.
Even Jesus who is, as a god, held to a high level of esteem by those who do not believe he was divine, damned entire cities do horrid deaths due to a handful of inhabitants not liking his message.
Luckily science is finding answers to the questions on the answer of where does morality come from, and at least right now it appears that a large portion is innate, or at least concepts like sharing and fairness and altruism.
My opinion is that the main challenge with morality in the modern world is that is less typical to extend that respect and kindness to those who you do not identify as a part of your “tribe” due to a lack of a better term.
Us humans are quite good at using irrelevant traits to mentally remove other humans from our “tribe”. We do it based on language, mythologies and even irrelevant differences like the amount of color in ones skin.