Headline: Why are so many feminists obsessed with their genitals?

A lot of feminist stuff is associated with female genitalia. There are vagina monologues, vagina hats, vagina boats, paintings using period blood, yoghurt made out of vaginal yeast, etc.
You don't see MRAs do anything similar. Even the most extremist people in the manosphere don't do anything involving penises. The closest I've ever seen was the Wiener's Out thing in South Park, which was a parody.
I wonder why. The expected answer is that women's sexuality is oppressed and stuff, but I really don't see any social situation where penises are more appropriate than vaginas. In fact, it's the opposite: Female nudity is more socially acceptable than male nudity, whether it's in art or in real life. Women who flash their boobs or vaginas are met with cheers, while men who show their penises to people are arrested.
Granted, men do draw dicks on walls, but they don't really do it out of celebration of their masculinity, and it's considered more of a childish thing. Drawing dicks is mostly associated with juvenile humour, while the feminist vagina thing is supposedly classy and deep.
What are your thoughts?