Often repeated but a provably false statement. I have reminded many that the first mechanical cotton picker was not invented until the 1940s, and it was not really a practical machine until the 1960s. Other crops such produce are still hand picked. And I remind you that the first African slaves were brought to the new world for mining. We have no shortage of mining ventures today.
Would slavery have lasted up until our day. I doubt it. I think there would have been a slave rebellion in the South before too much longer. It would not have been pretty and probably taken many more lives than the Civil War. But don’t for a minute think that mechanization would have brought a quick end to slavery. It would not have. There was still a demand for it.
I did not make the statement to which you are replying. I was quoting what someone else said.
And you are wrong. A cotton picking machine was made in the 1840s I think, but it was not successful. The point is, people were trying to do it, and with enough incentive, they might have made a successful one before the 1940s.