
Good find. I forgot about it.
But still it doesn't mean there are multiple human languages in the current times.
It's a moral boosting speech and what it does is reference that languages exist in the world, but not that they are used in Eorzea. Minifilia is making statements in a general or philosophical sense ("Languages are a barrier that divide people"), and not as a specific truth about current Eorzean society ("Eorzea is divided, by language and etc"). As far as we know languages may be a barrier that's been 'trascended' by Eorzea already, as they are not mentioned anywhere else.
But still it doesn't mean there are multiple human languages in the current times.
It's a moral boosting speech and what it does is reference that languages exist in the world, but not that they are used in Eorzea. Minifilia is making statements in a general or philosophical sense ("Languages are a barrier that divide people"), and not as a specific truth about current Eorzean society ("Eorzea is divided, by language and etc"). As far as we know languages may be a barrier that's been 'trascended' by Eorzea already, as they are not mentioned anywhere else.