I’m from Appalachia, buddy.
Don’t be so presumptive. A person can be from a poor background and care about racial justice. Don’t use my relatives and forebears as a “gotcha” tactic or a distraction from racism. They were mixed-race and wouldn’t want you to pull that crap.
It sounds like you need to re-read what I’ve written; you’re missing the part at the very beginning where I state that mental illness is implicated in these events. These variables interact. Mental illness by itself is not a significant predictive factor. It’s also worth reading up on the philosophy of science and how one goes about proving cause and effect relationships exist, too. Here’s a Cliff’s Notes: If only a subset of a subset of a subset of mentally ill people are violent, it’s not the mental illness that explains why the violence happens.