How many feminists does it take to change a lightbulb? As many as possible but they wont change anything.
What do you have against feminists?
They haven't changed anything ever, except possibly their underwear and that's all I need to know about them.
The world was revolutionized in the 60's by the feminism movement, so your assumption that feminists can't change anything, not even a lightbulb, is totally false. Take some time and study up on the feminist movement as I think you will find it enlightening.
They didn't change anything useful
They pushed for rights of all women in America and inspired some movements overseas. That is useful.