Again, where are you getting the numbers?
Somalia as a country is unstable and war-torn, and therefore it's population is subject to that and environmental upsets. The conflict being inter-Somali, it makes sense that Bantus would be more insulated from it to some extent, and to my understanding, Bantus due to their agriculturalist lifestyle (vs the Somali nomadic culture) were settled in the fertile parts all along? Even if your projections (numbers) are true, all of this makes sense in the context of what's going on, what doesn't make sense is the victim schtick and the demonization of those ppl for..breathing.