|This image is originally from http://themetapicture.com/brilliant-comeback/|
All credit due the creators and other such indemnification.
First of all, Brave is set in Scotland, not Ireland. I have relatives that would murder you for failing that distinction.
But with that
While it's true that it makes the most sense for the three protagonists and deuteragonist to be white for these three films, and also, for the bit and supporting players to be white in the contexts of the story, in the past four years Disney has failed to release a feature film in its princess pantheon with a non-white lead or a diverse cast. While the films are most definitely based on traditional fairy tales, every culture has a rich tradition of storytelling that Disney could've mined and adapted, but in four years, they've chosen from a strictly European formula. Also, stories such as "The Frog Prince" are from the same cultural landscape as "Rapunzel", but Disney storytellers set it in the Jazz age of New Orleans with a black protagonist, black villain, black mentor, white foil, and ethnically ambiguous love interest--more diversity in 2009 than 2014.
Additionally, while one could argue that old school Disney princess films such as "Snow White and the Seven Dwarfs", "Cinderella", and "Sleeping Beauty" skewed pretty closely to the original tales, "Frozen", Disney's latest offering, is set in the fictional land of Arendelle, with clothing, technology, and inheritance rights all suggesting an anachronism stew of time periods and locations with no real world counterpart. Kai and Gerda, the main characters of "The Snow Queen", upon which the movie is loosely based, are not even in the film, so loyalty to the source material is moot. Yet, all the characters were so white I barely noticed when SPOILER! the land was engulfed in an eternal blizzard. Clearly, while not actively whitewashing by refusing to update the racial makeup of Arendelle, Disney certainly isn't being progressive either.
As for the assertion that there are "plenty of ethnic Disney ladies", I invite the reader to check out the list of official Disney princesses here. If you'd like confirmation from the Mouse, there is a link here, that hasn't yet been updated to include Anna and Elsa. If you'd rather not distract from the brilliant wit that is this post, there are thirteen official Disney princesses, in order: Snow White, Cinderella, Aurora (Sleeping Beauty), Ariel (The Little Mermaid), Belle (Beauty and the Beast), Jasmine (Aladdin), Pocahontas, Mulan, Tiana (The Princess and the Frog), Rapunzel (Tangled), Merida (Brave), and Anna and Elsa (Frozen). Esmerelda doesn't count as a princess, being the love interest of her film instead of the protagonist (like Jasmine), and not being royal by either birth or marriage (like Mulan) and also because basically Disney says so. Note that out of 13 princesses, two are Asian, one is American Indian, and one is black, bringing the total to a whopping four. Let everyone be aware that 4/13 qualifies as plenty. Try arguing that point should you get that grade on a test--which would be a 31%, for anyone keeping track. And the fact that Tiana has no black friends to hang out with at the Disney princess parties, that Pocahontas is the only American Indian, and South Asian Jasmine and East Asian Mulan don't know any princesses who look like them, we've added up to that ugly little t-word: tokenism. If you break through the glass ceiling, but you're standing alone on the rubble with no one following behind, you haven't really accomplished much.
I don't want to live in a PC world, filled with stories and characters that have been flexed and molded to appease everyone and so please no one. I loved "Tangled", I adored "Brave", and "Frozen" warmed the cockles of my fairy tale loving but feminist heart. I wouldn't change a thing about any of them. I would want to see movies--and I mean feature films that are added to the official princess list--that feature characters as flawed, interesting, diverse, and heroic as Rapunzel, Merida, Anna, and Elsa with a plethora of skin tones and ethnic backgrounds. I want the rich tapestry of folktales and legends from Europe, Asia, Africa, Australia, and the Americas updated, adapted, and given a Disney ending. I want an upgrade from tokenism to diversity. I want Disney, the stamp upon my childhood, to stop whitewashing. And I want them to mean it.