It's pretty clear to me that they're just asking for slender/boyish aka what you see as the lead in nearly every JRPG and anime today. What you're telling them they actually want to play as is a tiny race of potato people, which this is not.
Body type they're asking for:

Body type you're telling them is close:
It's fine if you don't like or want that but it's not something that already exists in this game.
I think SE will just do whatever they please and lore and all that don't matter a lick in this game. They wanted more petite, cute girls so they made female Au Ra into that in spite of any lore reason. They wanted more tall edgy dudes so they made male Au Ra into that. They will do the same thing again if they want to.
That said, people can want something different regardless and I don't think they need to scan the lore to justify themselves. The only female races that looks like it could use half the weapons in this game are femroes and maybe elezen but like, who cares? We've still got little lalafells out there guarding Limsa and female miqo'te acting as the protectors and hunters in their tribes. It's clear little in this game is modelled with 100% practicality and deep lore reasons in mind. If someone is a petite dude in real life and wants to play one in a game too why do they have to feel ashamed of that? And they're certainly not the first one in this thread to say the same thing.
[Also only like, the first half of this post was directed at the quote. The rest is a general response to the last ~5 pages of this thread.]