Since the ample opportunity for self-correction was not taken, I’ll do it myself. The scores presented as “the average scores across the SAT exams” “to get into Harvard” are in fact the scores of applicants. You can tell by the “Among Applicants” and “Among Admits” labels in the legend for the plot these numbers were pulled from. When you mouse over them, there’s even a popup that says “Among Applicants” or “Among Admits”. These numbers are also averaged over the classes of 2000–2017. So the actual average gap over that range was 63, not 100. And the gap ten years ago in 2013 (for the class of 2017) was 51, down from 72 ten years before that.
So the numbers were wrong and the use of present tense was inappropriate.