Interestingly enough, in German "diverse"
can relate to an individual. This is a fairly recent development – following a 2018 court decision, "diverse" was introduced as a third option in census forms and the like, to be used by people who do not identify as "female" or "male".
Obviously, this doesn't change English language usage, and it wasn't what was meant here, or what H4 understood, but if you see or hear German speakers referring to "diverse people" in English, bear in mind that this may be what they mean.
Moreover, note that if you mention "diverse people" to a German speaker (saying something like "we need more diverse people ..."), they may be unsure what you meant, or misunderstand you.
Coming back to H4's point, and English as spoken by native speakers, The Atlantic has a cool article that expands on Ava DuVernay's comments, called "A Person Can't be Diverse". It goes more deeply into the linguistic aspects than the New York Times piece did.
Andreas