It all seems like the same Utopian thinking any way you cut it. It makes for good fiction books because we can't see the actual counterfactual.
The simpler explanation to me would be it wouldn't matter if you had a religious or secular society. Just different trade offs on the long march of progress.
People 80 years from now will live better lives than we do today. That is just the way it goes. Of course if you asked anyone during WW2 this 80 years ago about 2025 they would give a highly pessimistic answer about 2025.