No, not negative. It's an empirically proven fact that children of wealthy parents perform better in school. This is not up for debate.
What I read was a repudiation of the argument that on average poor children fare worse in school therefore a given child from a poor family will necessarily perform poorly. It is entirely possible for a poor child to outperform wealthy peers, and the behavior of that child’s parents or the culture at home may have a large effect on their performance.
Is it because they are wealthy? Or how about, how much of the difference (not quantified here) is because of wealth?
> "Culture" seems to be a byword for money here.
is what I'm disputing, which would imply that money will solve our problems.