I honestly don’t remember what kind of diapers were used in the 70s.
I wasn’t old enough to have kids in the seventies, and I didn’t think about diapers at all. If you had asked me, diapers didn’t exist in the 70s, for all I knew or cared.
My grandmother line-dried sheets in the summer, I remember that because we would play games where we would run through them and stuff.
My great-grandmother had a bag with clothespins (I think she wore it around her waist, if I remember right) and she hung clothes and sheets and stuff out on the line. She had a trailer on my grandmother’s farm (her daughter) and they used the same clothes line.
I have known a fair number of women who use/used cloth diapers in this millennium. They are mostly homeschooling, home-birthing, natural foods, back-to-nature, do-it-yourself, large close-knit families.