This would be a stronger argument if people were generally something close to perfect reasoners, and especially if they were so when subjected to terrible suffering. Unfortunately, that isn’t the case. In the face of terrible suffering people are frequently very irrational, and I wouldn’t attach much weight to what happens to their religious position in such cases. (They might, e.g., cling to religious beliefs they find comforting, even if the thing they need comforting because of is really very good evidence against those beliefs. Or they might abandon religious beliefs because they’re so badly hurt they can no longer conceive of such a thing as a good god, even if they have what are objectively very good reasons to think that their former beliefs aren’t invalidated by what they’ve suffered.)
Even very intelligent and reasonable people who generally try very hard to be skeptical and rational can be extremely irrational about things they’ve believed for a very long time, grown used to, and built their identities around. Political and (ir)religious positions are particularly liable to be held irrationally. If any part of your belief is founded on the idea that what lots of intelligent and reasonable people believe can’t be terribly wrong, you should reconsider that. The existence of lots of intelligent and reasonable Christians is, unfortunately, perfectly compatible with Christianity being obviously crazy when looked at objectively; the existence of lots of intelligent and reasonable atheists, likewise, is perfectly compatible with atheism being obviously crazy when looked at objectively.
(My opinion is that neither is obviously crazy, but that very few reasonable people would be much inclined to think Christianity likely to be right if they encountered it afresh without the influence of a culture saturated in Christianity, and if when they did encounter it they saw an unbiased selection of relevant evidence rather than e.g. meeting it through the preaching of evangelists whose goal is more to persuade than to inform.)
This would be a stronger argument if people were generally something close to perfect reasoners, and especially if they were so when subjected to terrible suffering. Unfortunately, that isn’t the case. In the face of terrible suffering people are frequently very irrational, and I wouldn’t attach much weight to what happens to their religious position in such cases. (They might, e.g., cling to religious beliefs they find comforting, even if the thing they need comforting because of is really very good evidence against those beliefs. Or they might abandon religious beliefs because they’re so badly hurt they can no longer conceive of such a thing as a good god, even if they have what are objectively very good reasons to think that their former beliefs aren’t invalidated by what they’ve suffered.)
Even very intelligent and reasonable people who generally try very hard to be skeptical and rational can be extremely irrational about things they’ve believed for a very long time, grown used to, and built their identities around. Political and (ir)religious positions are particularly liable to be held irrationally. If any part of your belief is founded on the idea that what lots of intelligent and reasonable people believe can’t be terribly wrong, you should reconsider that. The existence of lots of intelligent and reasonable Christians is, unfortunately, perfectly compatible with Christianity being obviously crazy when looked at objectively; the existence of lots of intelligent and reasonable atheists, likewise, is perfectly compatible with atheism being obviously crazy when looked at objectively.
(My opinion is that neither is obviously crazy, but that very few reasonable people would be much inclined to think Christianity likely to be right if they encountered it afresh without the influence of a culture saturated in Christianity, and if when they did encounter it they saw an unbiased selection of relevant evidence rather than e.g. meeting it through the preaching of evangelists whose goal is more to persuade than to inform.)