It would be hypocritical, but it may also be the best route moving forward. It's one thing for him to create characters when he had no idea how far his comic would take off. But now that it's his most popular comic, for which I'm sure he makes a pretty penny, I doubt he'd risk it just to bring back two characters he hasn't used for 90% of the series. He also stated that Sofia won't appear much after the Martha's House arc. It appears to be a lot of trouble for something many could do without.
Her skin color plays a factor in her attractiveness, just as Sarah's hair color, or Lana's skin tone, or Amanda's beauty mark, play a role in their attractiveness. It's a physical trait, so naturally it would. No shame in it. I'm not suggesting that Rosa get her own comic, or feature more in side-stories, because of some "DEI Quota,"; I like her appearance and her brown skin, and her curly (presumably coarse) hair factors into it, not to mention her face, breasts, and butt. I'd like to see more women of color (not just Black, but Hispanic, South Asian, Middle Eastern, etc.) because I think the associated cultural aspect can lend itself well to many incest narratives. I'm not knocking the "frustrated housewife" angle, but it'd be nice to see incest pursued in a different way.