tribal africa always had high birth rates. .. but also high deathrates. hense the need for high birth to counter the deaths.
this was not about democracy. this was about modern medicine.. or lack there of
tribes needed warriors/farmers so need to expand. but tribal battles/disease/famine decreased population. hense more births needed
India has the same problem and it usually falls to poor education, poor healthcare, no birth control, and small communities/impoverished villages will pump out as many children as they can. Maybe it's different in modern times but even if Africa gets their population under control, they still don't have a worth wild economy that would ever support African prosperity, and it's not like they have any resources to fall back on (no oil, natural gas, ect.) At most they have pervious metals, and that isn't as profitable.