I would dare say those states had record turnout themselves. If 2016's turnout was only 55.7%
according to Wikipedia, then imagine the impact of having a near 70% turnout rate. It's a considerable percentage, and considering the states still counting according to Fox are NC and GA, those states aren't tiny. They have many metropolitan areas of considerable size, so we're not talking about a Wyoming or North Dakota here.
I'll name some metros off:
Charlotte, Raleigh, Fayetteville, Greensboro and so on in NC.
Atlanta, Columbus, Macon, Savannah, and so on in GA.