Real heads been moving down to a ATL since the early 90s
As a native ATLien I can co-sign this. Even more, a lot of the ATL born middle and upper class are the children of transplants from the 70s-90s. My parents came to ATL in the 70s and growing up in South DeKalb, the hub of middle class Black folk at the time, I would say 70% of the kids I grew up with were children of transplants, 30% were from the old-school/local ATL middle class or upwardly mobile long time ATL residents. Even Mayor Bill Campbell was a transplant from NC.
Long-time ATL residents were often in Fulton, the most wealthy ones in Cascade, while whole neighborhoods built in DeKalb County in the 80s absorbed the first middle class Black transplants. A lot of the locals got into the middle class via jobs at the big companies when they were growing: BellSouth (defunct), GM (defunct), Delta, Eastern Airlines (defunct), Coke, UPS, and some others. But a lot of those jobs cut back, especially the former BellSouth, Eastern, and GM, so they had a harder time. Remember the only local HBCUs were the AUC which were also often majority out-of-staters too and GSU was just starting to get a Black population then so that helped attract people but also meant locals had limited options for higher education until GSU got much bigger.
The Black poor in ATL were often left behind in the white collar boom sadly since Black folks moving in probably accounted for a lot of that growth. I have family in both sides of the divide so I get it though I believe the opportunities that opened up in the last 30 years and the large Black community have helped locals get some mobility too.