Stacey Abrams was unopposed. She didn't need a single vote. If everyone who wanted her to win the general election voted for Kemp (a weak opponent in the general election) to beat Perdue, she wins.
Kemp won every single county in Georgia. He won ruby-red deeply conservative counties some of which vote over 80% for Republicans. There aren't even enough Democrats in these counties to swing anything, even if they all turned out for Kemp, which is obviously not true because Abrams did receive the usual number of primary votes Democrats typically receive in them. There was nothing abnormally low about her vote totals. There were competitive Democratic races for Lt. Governor and Secretary of State.
At some point, it becomes time to admit that Brian Kemp won the GOP primary because more Republicans voted for him than David Perdue last Tuesday.