Though I am not atheist, I say it is more chosen by humans, humans want to believe it, regardless of what the truth is, this is why atheism is more acceptable to secular based mindsets, people always focused on being as cutthroat as possible to become as rich as possible, people who don't like having to abide by morality, unfortunately these types of people are very common in our society.
A majority of the world holds religious values and the idea of having a religion is very comforting. I am an atheist myself, however I would like a God to be real. The only problem is I can't persuade myself to believe that. There is simply no evidence. Regardless, religion is more commonly held