Agreed. But it has become a wedge political issue that can drive support via moral appeals, so it’s useful for getting votes. At the end of the day, it sounds so simple - pro-life! How can anyone be against life but a nihilist! Plus, if you support pro-life, you get to feel like you are morally pushing against the establishment, and who doesn’t love to feel like an outsider rebel rebelling against the powers that be!
Grace Hale had a whole chapter on how religious conservative activists used the language of human and civil rights to garner support for their anti-choice cause in her book A Nation of Outsiders, which I regularly recommend cause I think is a great book about postwar American white culture and how we got to where we are today, with some many supposedly ordinary white people thinking they are cultural rebels against some mainstream establishment run by liberals, commies, and Black people: