In the 1800s, the North industrialized but the South did not. In the 1920s, the North electrified but the South did not. There is no reason to expect that the South would have suddenly changed in 1930 when it had not before if you totally ignore the New Deal.
Pre-Civil War, slave labor agriculture provided the highest returns on capital in the South. The economic dislocations caused by the Civil War exacerbated the problem as most of the South’s capital was destroyed by either war damage or abolition. It was further retarded by the sharecropping system and segregation which encouraged those who left rural areas to leave the south altogether. Rural electrification was a problem in both the north and the south prior to the REA which helped to jump-start the process.
