I'd rather think that they're enthralled by sexism and racism than that they're stupid. I think that's more helpful. There's no cure for stupid, yet, but racism and sexism are both issues that can actually be approached. Even if you need a big stick to approach some of these people.
You should watch her videos before you make that assumption (I know you have >_> I am saying that for effect). She isn't neutral in spite of her disclaimer.
Neutral? I have never seen her or anyone on "my" "side" claim they are neutral. The only time someone claims they are neutral is right before making some sweeping, unsupported statement about there not being any racism or any other form of oppression, that it's all in their head or something (or any other statement that's meant to deny some analysis). Because you can't actually point at a molecule of racism or any other social relation, so therefore facts, logic and truth are all in favour whatever reactionary standpoint the denialist is supporting.
No, I'm not neutral. I embrace my lack of neutrality. I have an agenda, I have a goal, I analyze things in a certain way, and I have no way of knowing the truth. I can only approach it. Anyone who tells you that they're "neutral" is full of shit. We're all very much subjective. Doesn't mean our subjective viewpoints are all worth the same, though, that's postmodern bullshit.
This is a bit of a rambly post. Short, though. We're veering way off the tracks, so there's that excuse.
EDIT: Oh. You mean Anita. Well. I can't say for certain what attitudes have contributed to attacking her. Sexism, definitely. Probably not racism, as you say. I was speaking generally about those kind of "stupid" people.