Most atheists/Christians aren't as rigid as you imagine.
> a universe where there's no doubt that there is no god
The vast majority of scifi (and other genres) doesn't care or take a position either way. Nothing in Blindsight says "there can't be a God"; it has nothing to do with that.
https://en.wikipedia.org/wiki/Hyperion_(Simmons_novel) is a massive classic and is full of that stuff. The Matrix has The One die and be resurrected as a godlike glowing being.
Most atheists/Christians aren't as rigid as you imagine.
> a universe where there's no doubt that there is no god
The vast majority of scifi (and other genres) doesn't care or take a position either way. Nothing in Blindsight says "there can't be a God"; it has nothing to do with that.