Actually, GA began trending D in 2008.
It’s shocking how little time GA was actually a Republican state as downballot it was Democratic until 2002 and Presidential since 2000(it was a swing state in the 90s).
It is very possible that GOP dominance of certain Southern states will look like a brief historical anomaly looking back from say, 2050.
In Virginia, easily the most Republican leaning Southern state during the mid-late 20th century, Democrats still controlled everything at the state level as recently as 1993. Republicans only had 4 total years of trifecta control, from 2000-2001 and 2012-13, and the latter time, they needed the Republican LG to break ties in the state senate! At least VA Republicans had the 1968-2004 streak at the presidential level, and the early wins in 52/56/60.
In North Carolina, Republican control has only been from 2013-17 thus far and it voted for Obama in 2008, breaking the 1980-2004 streak.
Even in Texas, the Republican trifecta only dates to 2003 and could plausibly be broken with the 2020 (state house of representatives) or 2022 (governor) elections.