It is ridiculous to assert that skin color is reason for any country's woes. I'll certainly give you that. In fact it is so ridiculous it's not even repulsive (to me).
I don't know what is happening in Honduras and El Salvador of late but the last time I looked at murder rates around the world South Africa topped the list.
In any case with a rate of 31.8 Romeo was right that South Africa is among the most violent countries in the world. Their rate is more than 6 times that of the oh so violent United States.
Now if he is arguing that their violence is due to the skin color, I agree that his argument is ignorant, but I'm not sure that he is. Are you?
Referring to the chart you provided, if you "click on the little diamond" next to Region, you will find that Southern Africa tops the list followed by Central America, then Eastern Africa, and Middle Africa.
But murder rate is only one indication of the health of a nation or region.
Let's look at economics.
Obviously there are more than one way to judge the economy of a nation but here's a chart of GDPs by continent
Africa comes in 5th out of 7 ahead of only Oceania (Didn't know there was such a continent) and Antartica (Didn't know it even had a measurable economy, and as it turns out it doesn't. The chart indicates its GDP is "N/A")
Interestingly enough, when one looks at GDP per capita, Oceania takes first place, while Africa is essentially last (Just above Antartica with it's population of 1,000 and no GDP).
There may be other ways to measure the economy of Africa, but in terms of GDP, the picture is dismal.
Here again, an argument that this is due to the fact that the majority of Africans are black is ridiculous.
I have little doubt that if we checked any number of other measures of regional health, Africa would be on the bottom.
I wouldn't argue that it's because blacks are inferior to other races because I don't believe it and because I would probably be strung up in my town square if I did, but there must be a reason or combination of reasons.
You dismiss the strong influence of tribalism, but it's there that I believe the answer lies. It can help to explain why some black Africans had no problem selling other black Africans to white Europeans. It certainly can explain Rwanda. How it has completely manifested itself in terms of retarding African development needs a lot more facts and thought.
Whether or not this is Romeo's argument is immaterial.
He was right though that South Africa is among the most violent nations on earth and that Africa has not emmerged from the colonial period as well as other regions.