” I did simple math: if “more people become non-religious than become religious.” Then eventually there will be no more religious ppl.”
You left people being born out of the equation. The frum population can grow even with a greater number of OTD’s than BT’s as long as the birth-rate exceeds the differential. The proof is in the pudding.
RSo’s point (which I agree with) is that it shouldn’t be surprising that people would switch to a group that allows them to daven late, not sleep in the sukkah, drink excessively, and call themselves “chossids.” That’s not a proof of emes that’s just a proof of easiness.