It refers to someone recognising the patriarcal systems that exists in the world.

A play on the term "red-pilled" based on the movie Barbie where Barbie is offered the learn the truth by picking flat Birkenstock (and travelling to the real world) or picking a a pair of pink high heels that reject that for keeping things as they are and ignoring reality.
I used to think men should be paid more but then I got Birkenstock-pilled and realised women deserve to be paid the same for equal work
by Kemal Shand August 17, 2023
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Any lesbian female (like Beanispenis) who wears manly sandals to attract other lumberjack-looking females with buzzcuts.
Birkenstock bulldykes run rampant in Colorado and New Mexico.
by Goonie's Revenge September 29, 2023
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