>Can someone elaborate the benefits/goals of using the feminine pronoun here?

Culture wars, but a much more gentle version than the current variety. There's definitely an agenda here as it wasn't done in any kind of unthinking organic fashion, especially given long-established norms (which weren't always male). Rather like replacing BC with BCE.

Some future historian will probably look at an AP style book over time and pass judgement on us all. Dunno how it will look. Maybe they'll think of the singular use of 'they' as implying that humans of this era had multiple personalities.