A lot of this dark crap is not so much because of evil facebook, but because the algorithms themselves only exist to give us (collectively) what we want. They are a dark mirror of society itself.
The research experiments have no bearing on what people type into that search bar billions of times a day.
I actually think the misogyny and regressive wingnut politics seeping into what we used to consider civilised liberal cultures is actually a reflection of the world population as a whole. Half the planet has a phone more capable and connected than computers that only nerds had in 1995, but most people still live in autocratic, repressive, patriarchal societies. The internet absorbs and spits back that influence.