I mean, playable races don't really adhere to lore. Male miqo'te are regarded as uncommon but a ton of players still make and play them anyways?
Playerbase has no correlation to lore because placing restriction on character customization for lore that Square Enix can make however they please would just feel oppressive. Like, "you can't play as a male mi'qote because they're rare just because we said so" would sound pretty silly and not be fun.
And suggesting that male viera should be gated off as a very difficult prize option when females are immediately available is uhh...