I liked it a great deal. I have enough bad things in my past to identify a little, and enough Scots-Irish in me to wonder about the genetics. He gives us a lot of what it's like to grow up among violent, clannish hillbillies, even when they have transplanted. His description of being a country mouse at formal dinners at Yale Law School are amusing, as is the suspicions-confirmed description of how networks mean all among the rich and powerful.
One of his main points is that even in terrible situations growing up, having just a few people care about you might be enough. This might be true. We certainly want it to be true. Vance looks at his own trajectory and concludes it was a near thing, and the absence of any of a short-list of relatives who were good to him might have been enough that he would have sunk beneath the waves. He wonders about the genetics of it all at the edges of his musings - why his mother collapsed under the weight of her parents' violence while her brother and sister muddled through and had decent lives; whether he may have inherited some worrisome weaknesses of hers - but in the end comes to mostly "nurture" conclusions about what happened in his own life.
As do we all. We can only see the environmental experience of our own lives, we can't see the genes. In a humorous irony, we are genetically programmed as a species to create a narrative from the materials around us. What we see becomes the basis for our story, even when it isn't really so. I don't mean to dismiss environmental aspects entirely. It can't be good to get beaten up, and it can't be good to be always worried about getting beat up. Expectations may have some effect simply because we all respond to incentives and disincentives. But these aren't clean measures. The person who beats you may have also given you their violence genes; the person who has high-expectations for you may also have given you their high-expectations/striving genes. In a larger culture this may be magnified as it is spread across anyone else your mother might marry or might be part of your peer group.
Cultures that are merely violent may not thrive all that well; certainly not in situations where they have to interact with other groups for trade. There has to be some ability for the group to put violence under discipline, or in a context, so that everyone doesn't just kill each other. Jim Webb's Born Fighting captures how this group of Scots-Irish have won America's wars. But Appalachian violence may not be entirely cultural and accidental. It might also distill as the less-violent move out, marry out, or find disciplines of sports or military. Vance makes reference late to intervening earlier with kids "raised by wolves." Government offering them college money looks good for elections, but by that time it is way to late for many. The trouble is that earlier and earlier interventions also don't seem to bear much fruit either. Maybe at the extremes.
He mentions that even though he wasn't often studying, the stability of living with his grandmother allows him to "ace his SAT's." Vance also notes that his mother was salutatorian of her high-school class, though she threw it all away with drug addiction and terrible men later. Those rather say "genetics" in bold letters. At the margins, being too drug-addled to show up for the test keeps you from acing anything, and fearing getting beaten might decrease your focus enough to miss some questions. Yet mostly, no.