You're quite correct in observing that the religious issue isn't even relevant to the actual abortion debate. Overturning Roe's viability standard can be justified completely on the basis that it draws the that line on about when the "fetus gets closer to being an actual person" in the wrong place. As the article observes, most of the developed world draws that line around 12-14 weeks, versus closer to 22-24 weeks under Roe.