I don't know how much I can trust you on Zuse if you can't get basic facts about de Beauvoir right:
Simone de Beauvoir did not have a "future is female" plan, as the modern slogan "The Future is Female" originated decades after her major works and stems from lesbian-separatist contexts in the 1970s.
"She is globally famous for writing in The Second Sex (1949) that "[o]ne is not born, but rather becomes, a woman," which established that gender is a social construct rather than a fixed biological destiny." (I hazard this is really what you're butthurt about).
"Rather than advocating for female supremacy or a matriarchal "female future," Beauvoir's existentialist framework sought human liberation and radical reciprocity between sexes, arguing that both men and women need to transcend oppressive societal myths of the "Other".
The phrase "The Future is Female" was coined by Liza Cowan in 1975 at a feminist bookstore (A Woman's Place) in Washington, D.C., and later popularized as a modern pop-culture T-shirt slogan in the 2010s, completely separate from Beauvoir's 20th-century existentialism."
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Trying to find info on a "90% male reduction plan" it looks like what you are referring to is:
The idea of reducing the male population by 90% (leaving a ratio of 10% men to 90% women) comes from the radical American feminist author and activist Sally Miller Gearhart. In her 1982 essay titled "The Future – If There Is One – Is Female,"
Gearhart argued that to achieve global peace and end patriarchal violence, the human sex ratio should be shifted over time. She explicitly clarified that this should not be achieved via violence or culling, but rather through future reproductive technologies and selective breeding
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Please don't conflate Simone's pluralistic, humanistic, liberating form of feminism with 1970s style "Lesgbian" RadFem ideology.
Please at least get your actors straight when you make claims like this, it almost sounds like I'd be making claims like: (bot) throw234259 wants to genocide every human and especially men.
It's not even remotely true. And it stains your name, because it's easier to just take what you heard without reflecting or retaining (even if google is a search away).
Eugenics is alive in the US Government right now. "Don't get injections, only the strong survive! Drink raw milk, don't you dare have government test it... Swim in Sludge (literal things RFK Jr advises/does)" The Kennedy's were literally eugenicist and threw his aunt in an institution and lobotomized/sterilized her.
If you want a "widely supported today" why didn't you take one of the chief proponents of such ideology as your example? One who hasn't been dead in ages? One who holds power, and is joined in a union with SecDef Pete Hegseth who pushes some "ubermensch" (I'm stwong!) Might-Makes-Right/Fittest-Survives ideology that closely ties in with this ideology.
I would leave it there, too, but you didn't.