It's that Merida (the character) is fiercely independent and as-drawn, is closer in appearance to a real girl. The "new" look trashes all that and is a retread

It's that Merida (the character) is fiercely independent and as-drawn, is closer in appearance to a real girl. The "new" look trashes all that and is a retread of all the current Disney princess tropes. In other words, she now looks like she was designed by a committee. "Need to lose the bow - we don't want to promote weapons." "Can we change her eyes to look more oriental? We need to appeal more to the Chinese market." "Why is her dress so dull? Can we liven it up with some sparkles & gold?"