Gender locked race?

[Kupocoubo]

Also find it ironically funny that people who would point to the in game lore as proof male viera will be playable also think feol or some other drastically different sub race is coming for Viera when the in game text clearly spells them out as the Rava and Veena, being differentiated by light and dark skin tones.

You forgot about the "young Elezen" stuff while Ravas and Veenas differ only with skin tones. Also, Feol Vieras don't look "drastically different" than the Ravas and Veenas, they are just shorter, especially their ears.
If the "young Elezen" like Vieras are the other sub race, and given how young Elezen are short compared to the adults, it's reasonable to think the other sub-race will be shorter Vieras -> Feol.