i don't agree with everything in the article, but the fact that naval technology in west and central africa wasn't at the required level is definitely one of the most obvious obstacles
the other issue is that most african rulers really were too ignorant to catch on to the scale and magnitude of what was going on
they didn't have the bigger picture or bird's eye view of the whole trade
that's not to excuse them because regardless of that if enough of them had objected to the trade in their own individual kingdoms or regions it would have died down eventually
that's just to point out another reason that they failed and made the poor choices they did
something slightly related:
a little known example of one group of africans working with ADOS is the agreement that Martin Delany and Robert Campbell of the Niger Valley Exploring Party signed with a ruler in a part of Nigeria, for the establishment of a settlement there:
"During the 1850s Delany moved from cautious endorsement of emigration within the Americas to planning African-American colonies in West Africa. He organized emigration conferences in 1854, 1856, and 1858, and in 1854 he published
The Political Destiny of the Colored Race, a pamphlet that recommended emigration. In late 1858 he sailed to West Africa, visiting Alexander Crummell in Liberia in 1859. In December of that year, in the company of
Robert Campbell, a teacher at the Institute for Colored Youth in Philadelphia, he signed a treaty with the Alake of Abeokuta, in what is now western Nigeria, providing for the settlement of educated
African Americans and the development of commercial production of cotton using free West African labor. Before the first group of settlers could leave for West Africa, however, the
Civil War broke out and the plan never materialized."
Delany, Martin R. | Encyclopedia.com
i understand why most people (whether ADOS or non-ADOS) would not know about this episode because it never materialized into something concrete
but the political will and the mutual agreement was there for the establishment of an independent state there
http://people.duke.edu/~ldbaker/classes/backtoafrica/documents/blacket1.pdf
just certain factors prevented this from coming to fruition