I don't know about "fair," but I'm glad that in the original 3 seasons Techna, Musa, and Flora weren't royal, Bloom didn't find out until later, and Layla and Stella were the only full fledged royalty. It seemed like it was madami down to each and not glorifying the princess role. Idk about the newer seasons though, it seems like each of them is a princess except for Flora? I have no idea since I dropped the ipakita after season 4.
Personally, I think it's fine just the way it is. If all of them were royalty, then we'd get the impression that only royal mga engkanto could enhance their magic to such great heights... but with Flora, Tecna and Musa being just as powerful and charismatic as their princess counterparts, we see that even those of normal blood can turn into legendary heroes.
I think I like them how they are because if they were all princesses, it wouldn't be as interesting and everyone would have to be called back to their kingdoms to settle dilemmas and stuff which I think will interrupt the Winx missions.
