Some more data after finding stuff on the GA site (I think this is all registered voters, not active, based on the column headers):
2016 - Black turnout 1,151,949/2,048,904 = 56.22%; White turnout 2,529,810/3,727,549 = 67.87%; 11.65% white turnout advantage; 45.54% black-to-white ballot ratio
2020 - Black turnout 1,373,543/2,290,365 = 59.97%; White turnout 2,924,829/4,029,156 = 72.59%; 12.62% white turnout advantage; 46.96% black-to-white ballot ratio
So in Presidential elections the current ratio is indeed a bit lower (huge caveat: this year's info is early voting only while the above past years are total voting including election day) but not nearly as drastic as sushihorn is making it seem. In fact the white turnout advantage went up from 2016 to 2020 when Georgia went from going for Trump to going for Biden. And you can also see that the white turnout advantage went up while their share of the electorate went down due specifically to what we talked about above. Their share of registered/active voters is going down.