I do not understand why the above quote is marked down (-2 points when I was looking at it). We may agree or disagree with certain arguments, but if an argument

I do not understand why the above quote is marked down (-2 points when I was looking at it). We may agree or disagree with certain arguments, but if an argument is well presented, or a quote from a mainstream publication, I do not see any reason to shout it down. Now, I abhor this distinction between the white and black population, but this may be because I grew up in a European country with essentially no blacks, and have not internalized the American history of the racial relations. However, if we remove the "white" label from the above quote, the argument sounds mainstream. I do not agree with it, however, and besides, see it as illogical: the second sentence neither follows from the first sentence nor contradicts it, and how it is a "fact" is unclear to me. No studies have been mentioned, so this must be pure speculation.