I'm not saying this as an advocate of religion, because I am not, but this graphic doesn't really make its own case. Absent any metric(s) pertaining to how a society's well-being is to be measured or discerned, it doesn't mean anything.
I'm surprised Africa is so non religious.
Yes, I was surprised too but just 9% non-religious means 91% religious. India is said to be just 86% religious everywhere and I see how open, rampant and annoying religion with its loudspeakers, aggressive donations, waste and deep penetration into politics is. It is easy to imagine how 9% non-religious in South Africa wouldn't count for anything.