I do not for one minute believe that 70,000 years ago man ONLY lived in Africa.
That is absurd to the maximum degree. At the end of their 100,000+ year run the Neanderthals were still around 50,000 years ago in Europe and elsewhere outside of africa. Modern man had already been around for a while at that time.
“I do not for one minute believe that 70,000 years ago man ONLY lived in Africa.”
Maybe the implication is that we are of the generation from Africa, which survived 200,000 years (so far).
There may have been others, on other land masses, whose entire civilization disappeared. Died out from drought, from cold, from disease, from whatever.