That's why it's never gonna happen, they don't have resources to support this population growth.
Which resources specifically? We are now exceedingly good at growing food, and water is just an energy problem (can use desalination or purification). Solar alone might be sufficient given the cost and efficiency curves.
And in the case of Niger, Mali, Nigeria etc, when their TFR would eventually cross the 2.1 limit of demographic transition according to the standard model nearly half the global population would live there at the end of this century. It is insane and completely unsustainable even when not taking climate change and ressources depletion into account