This is not a directly inspirational movie. It's one of those that show the dark and eerie side of the traditional femininity. Picnic at Hanging Rock (1975, Peter Weir) is a mystery piece with little intention to be empowering.
Nevertheless, being a story on a all-girl boarding school in 1900's Australia where the notion of being lady like in all circumstances reigns (based on a novel by Joan Lindsay), it cannot escape but to portray the restrictive nature of such life. It's a life where taking off your gloves in a hot day is already a rebellion. And taking a walk - a dangerous adventure.
Instead of treating it as a mystery piece, watch it as a metaphor of the female condition, so severe and unfulfilling that disappearing may seem like a good idea.