I agree, but I also think a smidgen of this is down to her looks as well. I've been asking why questions my entire life, and never got anywhere near that level of vitriol from anyone, and always been refereed to as "smart", but fortunately, I'm not a pretty blonde white girl on the internet.

I'm absolutely certain that more than a few of the people calling her dumb didn't think a single critical thought about what she said. They saw her face and hair and dived right into their "dumb blond" expectations.