The Jews in the concentration camps were already religious. Maybe they became more religious because they suffered a near-death experience. But what would be more surprising is if full-blown secularists who had never been inculcated with Judaism converted to Judaism in the camps, based on a religious experience. Maybe that reportedly happened in a few cases. The majority of cases, though, are more readily explained in terms of confirmation bias.
We search for reasons to keep believing what we want to believe, overlooking even mountains of contrary evidence. The Romans' destruction of Jerusalem was powerful evidence against monotheism (link below), as was the Nazis' final solution. But Jews have been expert at explaining away negative data since they made a myth out of how they've repeatedly been conquered by foreigners. Jews deemed themselves God's chosen ones. They were chosen to be God's suffering servants or beacons of righteousness.
Jewish faith isn't shallow, but it's never been about the mere objective truth of theism. Jews crafted a literary universe that kept their spirits up throughout the centuries, amidst their many catastrophes.
In my many writings on religion, I often distinguish between exoteric and esoteric faith and practices. The former is literalistic and naïve, and I focus on refuting it. The latter is more philosophically sophisticated or mystical, and it's often consistent with atheism.
What's different about the animistic pantheism I envision is that it would be based on existential philosophy and on scientific objectification of nature, rather than on naïve personifications. This religion would be worthy in literary, aesthetic terms, meaning it wouldn't be cliched, archaic, and irrelevant to modernity.
As I already explained, I don't subscribe to the scientistic prejudice. What's scientistic about saying that theism is redundant for cognitive purposes? I've argued elsewhere that religion has social functions, so even if theism adds nothing to our knowledge, it could still be useful in domesticating human herds.
