kins, I don't think it is about intelligence, really.
The concepts are simple.
It's hard to accept them, yes, but that's true of loads of things. I don't struggle with basic arithmetic now but I did when I was 5. If I'd been taught this stuff from age 5, I'm sure it'd be exactly the same.
What I mean by the bell curve is - the way intelligence is measured, most people are of average intelligence. Then, smaller numbers fall above and below average. So there's a peak, where most people are, and that's average. It's more uncommon to be either less than average intelligence, or more.
I firmly believe the vast majority of people are capable of understanding feminism in terms of the concepts. I don't see any evidence that the brighter you are, the more likely you are to accept it. There are a lot of very bright people who are very sexist, and there are plenty of people on MN, who have children whom they know to have severe learning difficulties, who've never heard a sexist word from those children.