I don't know if this veggies first or fruits first is kinda like doctors saying at one point it's better if a baby sleeps on his back and then doctors saying that it's best if a baby sleeps on his stomach. I know my little sister and I were both raised on veggies first and then fruits. I love both, my sister doesn't like veggies so much. On my mom's side of the family it was always veggies first. My grandma said it was because babies start out eating bland foods and veggies compared to fruit are less flavorful.
I've gotta funny story to tell. As a baby my lil sis liked veggies a lot (remember now she doesn't). She loved carrots, sweet potatoes, squash, any orange colored veggie. She wouldn't eat anything else. This went on for a while and she turned orange
My mom took her to the doctor and the doctor said it was because she had too much beta carotene.