At the end, when he said, "Frankly, my dear, I don't give a damn," the audience actually gasped.
It was a "time machine" response.
GWTW is still my favorite film of all time. I first saw it in theater around 1963, ’64 as a teenager. It was the first time it had been shown since 1939 and I too, remember the women in the audience sighing when Clark Gable first appeared on the screen (some two or three years after his death). The women, like my mother, were teens themselves when it first came out. They aren’t any movie stars like Gable, The King, today.
It was years before they finally showed GWTW on television, then of course I bought the VHS tape version, and later the DVD when it came out