So many takes, so many good lines
It's actually not about slavery at all
A rarer view might be the economic point of when post-war, Scarlett begins to become a businesswoman.
She's being: * feminist * using trade to heal wounds w/the north * trading even with the evil yankee carpetbaggers, ending up making everyone rich * it's a bit against the story that the movie shows her using convict labor (depicted by white prisoners) as a replacement for the old slave-laber system
Somehow despite itself the movie is making absolutely clear and true points about how free enterprise is the way to heal old wounds, as a viewer you feel that what she's doing is wrong. The movies casts the old slave labor aspersion at northern-style business, somehow, DESPITE the north just having fought a war which among other things, ended slavery. So, this scene is really really stretching to make its anticapitalist point - even though here capitalism was the thing which defeated slavery, this time in N.America just as it had done the same making the british empire rich enough to defeat and ban it worldwide.
I haven't looked it up but I assume there are a bunch of people with communist sympathies involved in its production.
The emotional side
As melodrama this maybe sets the stage for everything that came later. The two are SO over the top in their rude and sarcastic remarks to each other. Anyone who's been in an argument that somehow spirals out of control will sadly see reflections of that in the way these two talk so extremely roughly and so proudly to each other - her in her immediate flight to claiming extreme self-reliance the moment her frame is challenged, and his, not so directly but it's there, in how at every moment when he is challenged to deal with someone's emotional storm, or attempt to soother her, he refuses and instead runs off to his prostitutes. It's the same lesson as has always been - that as the guy, sure his extremely bold, proud and high-handed approach to her, never taking her seriously works to attract her interest at first, while also being ofc tall, extremely bold, daring, admired but also an outlaw, but never forget also super rich, that in the end, to truly have a relationship he's really got to be her rock and learn how to soothe her. Despite all appearances there are eventaully things that can make her temporarily not be so extremely selfish (which may read as a rational approach to poverty, at least, as the completely bullshit line about "before what war and poverty did to you" would claim, but you'll note, she was even worse as a person before the war as a rich heiress. So poverty had nothing to do with it, in fact it improved her (given that she survived) - at least she knows how to work and is willing to get out an do things now.