Frankly, I’m a little surprised to hear you state your skepticism of the idea that atheists and agnostics can be more compassionate than Christians, given your willingness to admit just how many un-Christian Christians there are.
If the majority of people who self-identify as Christian do not exemplify the compassion that a true Christian would — if a great many of them are assholes, as you say — is it so hard to believe that the truly compassionate people among those congregations might be put off by those attitudes, and choose to leave, or to even question the faith itself?
A great many of America’s Christians seem to have a deep-seated xenophobia that just doesn’t seem to exist in the same numbers among the non-religious.
My father’s Southern Baptist church, for example, has some of the most generous and charitable people you will ever meet — provided that you are someone who resides within their in-group. If you happen to have the misfortune of not being straight, white, and Christian, then God help you — because these so-called Christians certainly won’t.
It is xenophobic attitudes like that which drove myself and many more people from my generation away.
What does it mean to be “compassionate” and what actions or values were measured?
There have been several studies which have demonstrated that phenomena, but the one I was thinking of was this one, which found that children with no religious training are kinder and more generous than their counterparts who have received religious instruction.