I asked one of our patients who was 101. I had to ask several times as she is hard of hearing but sharp as a tack. She said the washing machine, which is understandable, years ago with large families doing the wash was an all day back breaking affair. Just making cheese or soap was difficult.
Birth control is right up there for me. It freed women so much.
I love a warm house in winter and cool in summer.
Another very important one is pain meds, penicillan, and ether, imagine what surgery/ dental work was like before patients were put to sleep.