Yeah, this is not a good explanation at all, bordering on racist honestly. No data cited for claims, and plenty of counterexamples to disprove the point easily.
What, exactly, about the post is racist? The parent cited specific biological characteristics. Generalizations are not racist. Nobody claims it's racist to say that Kenyans tend to be good runners because of genes. In fact, The Atlantic made that claim [1]. The parent poster is making similar types of claims as The Atlantic article.
Where is your data? Where is your evidence for this borderline racist claim? Africa doesn't have strong teams, clearly your explanation falls apart with the slightest analysis.
Africa has the fastest teams, that's for sure. There are other factors that go into a team's success other than region, I definitely said speed is an important factor among others right?
To have elite running speed you need to have a higher torso/leg ratio, basically long legs and a high center of gravity.
There are regional differences around the world with torso/leg ratios. China is on the lower end, much of Africa is on the high end.