It’s S’no White

The problem is not that she's hispanic, but that her skin is too dark. They could've hired a pale white hispanic and it wouldn't really have mattered. Ideally, she would be a white European (it's a European fairytale, right?) although there are many Spanish Europeans. Even many "white" people would have skin that's too tan to play Snowhite.

They make this movie with the future generations in mind and the fact is, the future is brown: people of color (Indians + Chinese specially) far outnumber the number of white people in the world. As the human race continues to mix, racial ambigiousness will be more and more prevalent with a lot of people having a light brown shade of skin, sort of like Latina people. They have this in mind when erasing white people from their stories in favor of darkers skin characters.