To be fair many of us arrived at the idea that AI was humanities inevitable endpoint ahead of and independently of whether we would ever see it in our lifetimes. Its easy enough to see how people could independently converge on such am idea. I dont see that view as related to atheism in any way other than it creating space for the belief, in the same way it creates space for many others.
Id love to believe there is more to life than the AI future, or that we as humans are destined to be perpetually happy and live meaningful. However I currently dont see how our current levels of extreme prosperity are anything more than an evolutionary blip, even if we could make them
last several millennia more.