One reason that's not being said: HYBRIDS EVERYWHERE. There would be people speaking out "my wanted hybrid combination isn't in the game!" Everyone always seems to focus on lalaqote, but personally I'd love to see an AuRa/Roe hybrid from Doma(Raen or Xaela is fine). Elezen/Hyur hybrids already exist, although there's only one that we know of.
Think about it from a dev's point of view. You spend 2 years working on a beautiful AuRa/Roe hybrid, and no one plays it. The only hybrids being played are Lala/Miq and Elezen/Hyur. So that dev time to all those other hybrid races were wasted. It wouldn't be realistic to say "oh, only Hyurs and Elezen can hybridize with each other, and only Lalafell and Miqote can with each other". Go all-in or nothing, and if the devs feel too many of the models wouldn't be used then it would be more worthwhile to spend that time working on other aspects of character customization.
