The guys in armor are using guns. There are skyscrapers, cars, technology of the modern era.
It's contemporary. Nowadays there are people in various countries who wear traditional dress. Doesn't mean the year isn't 2015.
Main male characters get to be hardened soldiers, princes with fated destinies chosen by gods, sports stars, former generals, mercenaries, etc. That's just backstories. It's 2015, and the main female character of Final Fantasy 15 is a trophy princess. How embarrassing it must be to stand next to Mirror's Edge, Horizon Zero Dawn, and even Assassin's Creed! Seems like not only is 15's technology stuck in the past, so are its female characters.
If you would like to argue that Luna's hypothetical future possible actions excuse her character base as a trophy princess, feel free to do so. Of course you'd be ok with it, because to you, the female characters don't have to be characters you'd like to be or play. After all, you don't play any female characters in this game.