Africa has a number of factors in its favor that make it a potential economic powerhouse. It has some of the largest natural resource reserves in the world, it has a huge population, it’s conveniently located on or near several important trade routes.
It’s also cursed with some pretty bad natural infrastructure. The rivers in Africa don’t provide good access between the center of the continent and the coasts.
China had about the same GDP a Sub-Saharan Africa in the early 1990’s https://data.worldbank.org/indicator/NY.GDP.MKTP.CD?end=1996&locations=CN-ZG&most_recent_value_desc=true&start=1960 It’s taken China 35 years to get from there to it’s current spot as 2nd largest economy in the world. And that was for an economy that was growing at nearly 2x the rate of the rest of the world for most of that period. https://data.worldbank.org/indicator/NY.GDP.MKTP.KD.ZG?locations=CN-1W
That’s not to say that Africa can’t become an economic powerhouse but it will take a lot of work and time. It would take sustained investment and reinvestment in Africa over several decades.
Nobody builds cars under slave like conditions. It’s just not possible. Modern car factories are highly automated plants that require skilled operators. In the case of the VW Xinjiang, that was QC inspectors. There’s no way a hole in the wall car factory using outdated labor practices can come close to competing against modern production.