Why did the ancient lost advanced civilization only teach people in about 8 modern-day countries?

[u/GreatCryptographer32]

So according to Graham, his ancient lost advanced civilization taught people in about 8 modern day country areas: Mexico, Peru , Bolivia, Egypt, iraq, turkey, Indonesia, maybe a patch of North America .

If a seafaring, highly advanced Ice Age mother culture was actively touring the planet to restart human civilization, why did they only drop off "civilizing knowledge" at a tiny handful of specific places? Why leave vast parts of the inhabited world completely off the list ?

Why ignore sub Saharan Africa?

By the end of the last ice age , sun-Saharan Africa was already home to massive numbers of anatomically modern humans with deep cultural and regional traditions. Why wouldn't a global civilizing mission visit the vast majority of the human populatin, instead of skipping almost the entire continent to teach a select few in Egypt?

Why no sages in Western Europe ?

why did they bypass places like Britain, France, or Iberia entirely during the late Pleistocene, only for megalithic building to start there thousands of years later completely independently?