So why in your opinion are the majority of Jews non believers?
Personally I find this a really interesting topic. But I think when looking at it, we have to understand that Judaism functions very differently than Christianity in a number of ways. I don’t think that particular study is telling us that the majority of Jews are “non-believers”. I didn’t see the number percentage of Jews who are athiest (I could have missed it). I think the point of that study is to determine what it means to identify as Jewish. And that shows what I think most of us already understood: Judaism is as much a people as a religion.
As for “believers”, I think we have to be cautious in phrasing, because Judaism and Christianity don’t see “religiosity” the same way. As Christians, “belief” is what defines us. It defines us as Christians, and it defines the kinds of Christians we are (Eg. does someone believe in sola scripture, papal authority, consubstantiation or transubstantiation?) That’s why our theologians spend so much time on doctrines and working out the relationship between the persons of the trinity, what we believe matters. In Judaism, what constitutes “religious” is not the same, and it varies some among the different movements. The differences are more in practice and adherence to the Halacha and Mitzvot (Laws and Commandments). Theological differences are
almost entirely about those 613 commandments, which are necessary, which were necessary and are no longer relevant and should be adapted, and what would be considered (in Catholic terms) tradition vs Tradition and unnecessary altogether. So in some circles not practicing all 613 mitzvot would be a sign someone is a non-believer, in others, practicing Mitzvot is a sign of adhering to tradition and not a sign of “belief”. Judaism tends to dineneate more along “observant” / “non-observant” continuum rather than a “believer”/ “non-believer” continuum.
Even if we did look at the number of Jewish “believers” vs “atheists” I think it still wouldn’t be an equal comparison to Christianity. When a Catholic becomes an atheist, Buddhist, Baptist, etc, they stop identifying themselves as Catholics. Even though the Church still considers them Catholics, they don’t. In Judaism, it’s similar in that if someone becomes an atheist they still remain Jewish. The difference is they often still self-identify as Jewish. There are people who identify themselves as “Jewish Atheists”. But we don’t have anyone identifying as “Christian Atheists”
So I wonder if that makes it seem like there are more “fallen away Jews” than “fallen away Catholics”.