the AP exams began in 1955 or so (hard to find dates), so that's 112 years.
Except the quote was:
that would be standard fare in a modern high school course in AP calculus.
So that's some more years, but I don't think it's really germane. I'm not saying that the time gap proves she's a genius; rather, the time gap makes it harder to ascertain.
On another not-imo-germane-to-the-discussion-note, mathematics education was more or less overhauled during the post-war period in many countries. Mathematics education as an academic discipline, I believe, was an innovation of Klein's that fell out of his work in geometry.
Today is Ada Lovelace Day, when STEM enthusiasts highlight the work of modern and historical women scientists, engineers, and mathematicians. If you run a blog, you may want to participate by posting about a woman in a STEM field whom you admire. But I'd love to have people share women scientists/mathematicians/authors in the comments that they think we could all stand to read more about.