I’m sympathetic to your position. Note, however, that the causal origin of a belief is itself a question about which there can be disagreement. So the same sort of considerations that make you give epistemic weight to majoritarian opinion should sometimes make you revise your decision to dismiss some of those majorities on the grounds that their beliefs do not reliably track the truth. For example, do most people agree with your causal explanation of pro-Christian religious fervor? If not, that may itself give you a reason to distrust those explanations, and consequently increase the evidential value you give to the beliefs of Christians. Of course, you can try to debunk the beliefs of the majority of people who disagree with your preferred causal explanation, but that just shifts the dispute to another level, rather than resolving it conclusively. (I’m not saying that, in the end, you can’t be justified in dismissing the opinions of some people; rather, I’m saying that doing this may be trickier than it might at first appear. And, for the record, I do think that pro-Christian religious fervor is crazy.)
I’m sympathetic to your position. Note, however, that the causal origin of a belief is itself a question about which there can be disagreement. So the same sort of considerations that make you give epistemic weight to majoritarian opinion should sometimes make you revise your decision to dismiss some of those majorities on the grounds that their beliefs do not reliably track the truth. For example, do most people agree with your causal explanation of pro-Christian religious fervor? If not, that may itself give you a reason to distrust those explanations, and consequently increase the evidential value you give to the beliefs of Christians. Of course, you can try to debunk the beliefs of the majority of people who disagree with your preferred causal explanation, but that just shifts the dispute to another level, rather than resolving it conclusively. (I’m not saying that, in the end, you can’t be justified in dismissing the opinions of some people; rather, I’m saying that doing this may be trickier than it might at first appear. And, for the record, I do think that pro-Christian religious fervor is crazy.)