That might make a reasonable case, or at least one I might find difficult to defend against. Tragically, however, I've been an atheist from even before I found there was a word for it.
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'