To be honest, West Africa was pretty on-point in all of these respects historically. Especially along the Sahel but even to some extent in the tropics. Once you went south of this particular line the tsetse fly among other issues made creating any sort of "advanced" societies pretty prohibitive even though Bantus still managed to do an impressive enough job in some cases:
It's no shocker that European settler colonialism only really proved feasible and successful below that line and even then was not remotely as successful as in Australasia and North America where they mostly encountered Hunter-Gatherer populations. Most of the societies above that line had too high population sizes thanks to intensive enough agriculture and pastoralism, and through trade and some of their own industries had access to gun powder weapons. Cadaans themselves knew this and wrote reports about how infeasible it was to settle places like Egypt, India, the Horn, China or West-Africa.
West-Africa is, frankly, one of the main cultural cradles of mankind comparable to the Fertile Crescent, Eastern China and Mesoamerica and mainly lagged behind in terms of monumental architecture:
They're not all that irrelevant on the world stage either despite the incredibly extreme wealth inequality that we're all heading toward worldwide, make no mistake. Nigeria, their Germany of sorts, is the most populated country on the continent, is part of OPEC, has produced billionaires and has urban centers about as massive as those of some the Asian countries other than China, Japan and South Korea,
the latter two of whom pretty much got handheld and developed by the West.
What the two regions went through in the last few hundred years is nowhere near comparable. It's frankly dishonest to even try to compare them in the simplistic manner you just did with this short paragraph. You're also completely glossing over how much the USA pretty much propped up and created Asia's two main success stories within the last 65 years as I pointed out above. Japan's current development isn't due to its Meiji Restoration. Japan was finished after WWII. The US propped it up as a satellite of its global empire. This is historical fact. And mostly the same goes for SK.
Once you discount these two and the libaax that was always going to be China, Asia is not in reality that ahead of SSA. Countries like Thailand aren't even going to see "first world" wealth and status before their population begins declining. They're just more "developed" than SSA on the underdeveloped scale in part due to being right next to those Western propped up success stories and China but who wants to flex "I'm less poor than you." ?
