I think many commenters are misunderstanding the article. As far as I can see, it's not against the casting of babe roles in scifi. The complaint is that in a multi-species main cast, the male characters, while certainly including some beefcake, will likely ALSO have a lot of diversity and extremes of phenotype, while any female character(s) are likely to be relatively more heavily anthropomorphized, if not plain human, and fit the one body type.
Photograph: Allstar/Lucasfilm/Sportsphoto Ltd
This has happened with other mixed-species scifi "super teams" too: Star Wars, Farscape, Andromeda, etc. As a general rule, it appears that xenomorphism in the main cast is more likely and more extreme with male characters than with female ones.
I'm guessing that one of the main reasons this happens is that mixed-species main casts in scifi -- because of the shows' intended audience of human males -- tend to be (a) disproportionately male and (b) disproportionately human, with the central characters almost always human or practically indistinguishable from human. If you only have one or two females on your team, and you need to have some potential for a romantic subplot for the human male lead, you can't make make them sexually incompatible from a biological perspective. If FemRocket, FemChewbacca, FemBem and FemPilot were the only females in their respective casts, pairing them with a human character would be imagined as some kind of zoophilia. You might argue for intra-species non-human pairing, but given that multi-species casts also typically have at most one of each non-human species (scifi tokenism), that does not look likely to happen either.
The only solutions I can imagine would be more visibly non-human leads and/or more female main cast members. And maybe junking romantic subplots, but I doubt we will ever see that day.