I don't know how you could say that, considering the many horrible things taught because of or done in the name of religion over the millennia. Like, to use a recent issue, the biggest thing stopping gay marriage in the US at least was people's religiously driven belief that homosexuality is morally wrong.
I know many will say, "well it's only nominally driven by religion, people would've done [bad thing] regardless". But that's a clear double standard, if you don't also say that people would've done good things regardless.
I'm guessing the truth is both: sometimes people really would've done bad or good things anyway, the religion is just a cover. And other times, they really were driven particularly by religion.