I have no clue about percentages but it hardly matters since every case is unique. His mom failed big time as she was the first responder for him. Was she prepared for motherhood? Did she come from a broken home and never had a decent role model? Did society step in and give her the guidance she needed to be an effective parent? Did the school just send home a report card and assume his parents will know how to handle it? Did society give the school the resources to deal with the issues?
It takes a village to fail a child.
So you think society, not individuals, are to be the determiners on how to be an effective parent? I whole-heartedly disagree. You're very collectivist in your rhetoric here. Sure, a child can flourish from being a part of a "village", but the responsibility for the child isn't the village's, it's the parents, and the child themselves.
Meanwhile, that's quite a rabbit hole you're going down suggesting a broken home and role mode. While you're correct in the assumption based on data of single-parent households in the black community, you also seem to admit that it's not a good setup. So, we have a specific culture that is well above all others in producing poor family environments... what do we do? Do we encourage them to provide better family situations? Or do we enable it further by catering to it. You seem to want to do the latter, while at the same time acknowledging it's not good.