And it doesn't even have to be much more than very common things like most kids not wanting to stand out from their peers, at least not in any way that would bring the wrong kind of attention to them. If you grow up in a place where being smart and studying and caring about your education is very much not the norm, and gets you that wrong kind of attention... If that effect is there in the family as well, all the worse.

Yeh, some kids can manage to get past that, but it would be in all of our best interests for it not to require extraordinary efforts above and beyond just the already substantial work required to achieve the goal at all. For most of us in the middle class and upwards, it's more likely to be the case that we just need to do the work itself, we don't have to fight a whole other battle on top of that. Of course plenty of even those folks still can't quite do the work itself, so how many fewer when the barriers are even higher.