It's possible they were referring to the original New Mutants, of which three out of five were non-white. (Dani, Shan, 'Berto, Sam and Rahne.) A year or more later, after Ilyanna and Amara and Doug joined up, yeah, it got blonder and bluer-eyed, but the team started out in a really diverse place, and one of very few teams that had more girls than boys. I mean, your picture there is so far in the team's future that
Magneto is in it, so it's hardly representative of where they started out (or where they are now, for that matter, since Magneto as their headmaster is like a blip in their history that I'd honestly forgotten, although my hat's off to the artist for managing to obscure the
brain-scorchingly bad costume he was wearing back then, which I totally blame for my forgetting that era of his history).