Less religious societies are better off, that isn't up for debate. That certainly tells us that religion is not needed for a good society. Although I think there was evidence that the better society came first and religion was more of a defence against a cruel world. When your society became better and there was less fear and uncertainty then people no longer needed religion as a sort of defence system.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
Less religious societies are better off, that isn't up for debate. That certainly tells us that religion is not needed for a good society. Although I think there was evidence that the better society came first and religion was more of a defence against a cruel world. When your society became better and there was less fear and uncertainty then people no longer needed religion as a sort of defence system.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~