I didn’t grow up in the south but my father did (born 1919) and his family did have a full-time maid who helped raise him. Nor were they wealthy; my grandmother supported the family. I think maids were a lot less costly back then. FWIW, my father was caucasian and the maid was black; I imagine that part of the way it was affordable was the pay differential between the races.
Me: born late 50s, northeast; we had a once-a-week cleaning lady for a few hours. My mother did not work outside the house until I was 12 or so and then only part-time.
One of my professors told us how he had a black nanny/housekeeper as a child growing up in Pittsburgh. He said he used to love it when she would let him spend the weekend with her family in the Hill District.
Other than that, I don’t know ANYONE who ever had a housekeeper-black or white.