SC is the only state which became whiter during the 2010s. It's very unlikely that Democrats win it anytime soon.
And weirdly enough it moved to left because the incoming whites are more Democratic than the native ones.
I think GA, AZ, and NC, now swing states, become solid blue before SC, Texas also becomes blue before South Carolina too.
True, though in all honesty, SC shouldn't be that far behind the rest of the Atlantic South. It goes to show how much retirees have affected politics in the region. Georgia has Atlanta which has been one of the fastest-growing metros numerically. And I think NC's stagnant trend can be blamed on young professionals breaking even with retirees while SC's growth is probably a good chunk retirees.
It hasn't moved to the left, though. It went from Bush+17.08 (a R+14.62 lean) to Romney+10.47 (a R+14.36 lean), to Trump+11.68 (a R+16.13 lean). There's no reason to expect South Carolina to trend Democratic in the near future, and Democrats who think it's the next Georgia are mostly delusional wishcasters who think every state is trending Democratic.