I don't see how you leap from "She didn't have the power to stop Disney doing this" to "She had a small part in letting this happen." The only part she had is making a movie with Merida in it. The rest of it is 100% Disney's call.
While it's not her fault that Disney decided to make stupid changes, she did give them those rights when she signed her contract with them. That's the small part I'm talking about.
Yes, as I said: She made a movie with Merida in it. That did not in any way push Disney in this direction. They made that choice all on their own. Her part was putting Merida in the movie — she had no part in the decision to change Merida.
No, but she could have shopped her project at Dreamworks or Fox and said "I'll give you my project instead of to Disney if you let me have some say with how you use my characters after the movie is made".
-- edit response below was to some text that appears to now have been deleted from the parent
>> You're essentially saying, "Well, she shouldn't have been walking alone at night if she didn't want the consequences."
This again? Come on. When you sign a contract most of what can or can't happen is already spelled out. You don't sign a contract unless the stuff you're getting back in return outweighs or balances with the stuff you're willing to giving away. A reasonable person walks into a contract like this with a lawyer and knows exactly what they're getting into. This isn't the same as signing some credit card application where you don't get to make modifications to the contract.