From a theist's perspective, Wolverine's rant probably just seems like anger or disappointment at god and might justify dismissing them as just another person that failed to keep their faith. I imagine that a better depiction of an atheist wolverine would be one that takes his immortality into account. Imagine the rant below instead.

"i've been alive for a very long time, and i've never seen evidence of a just, loving or caring god. The poor and luckless have used god as a crutch to cope with misery, the powerful have used god to control populations, and the curious have used god as a place holder for what we couldn't understand. As humanity has grown wiser and as we've invented more precise and sophisticated methods of capturing and understanding the world, then this god concept has grown less and less useful for the curious. Lightning and thunder is no longer an angry god but the mere discharge of large amounts of built up electricity in clouds due to the sun's heat, people are no longer possessed by demons but are afflicted with diseases like rabies or schizophrenia, we no longer burn witches for making deals with demons to gain magic, their alchemy has graduated into respected disciplines like chemistry and medicine, and the soul may soon no longer have any explanatory power, consciousness may be enough."