Slavery would have died out simply because it is more expensive to keep slaves than it is tractors, picking machines, and a cotton gin. It is the "engines of progress" that would have made slaves obsolete.
Thats a great philosophical discussion. Tell that to a slave in 1860 who had no hope of being free any time in his lifetime.
The Confederacy was wrong, and its good they lost.
true, but steam driven tractors didn’t come into use until 1890s and a successful cotton harvester was not invented until the late 1920s. So by your criteria, slavery might have lasted into the 1930s.