Appalachia is poor as dirt, yet has half the crime rate. And that's just one comparison - there are lots of others in the world.
Crime is a meme (in the Dawkins sense). You see your peers memeing and you start to repeat the same meme yourself. The more you're surrounded by the meme, the more it becomes part of you and how you operate. It's how our brains operate as pattern recognizers and pattern repeaters.
The spread of school shootings is a meme - it didn't happen in the pre-internet era, yet the uptick in news about it has led to a proliferation. It's become a part of the public consciousness, including amongst those that feel disaffected and likely to fall into destructive patterns of thought. It's easy to find online communities that reinforce these feelings and dispositions.
"Incel behavior". Meme.
Anti-trans politics. From out of nowhere, it's suddenly everywhere. Also a meme.
Through this lens, gang behavior amongst disaffected youth is no different than shitposting on Twitter in how it latches on to people and spreads.
If you transplanted the seeds of Atlanta crime into Pickens County, Georgia, I've no doubt the same behavior would take root there. It's independent of skin color or genes. It's a brain modality.
Behavior spreads as a meme. If there are pockets that support or reinforce a particular behavior, then the fire can't and won't die out.