It's my understanding that most people in Eorzea- the average Eorzean, at least- are illiterate. Player characters/adventurers are special, of course, so I guess that's why most RP characters conveniently can.
Most of my characters are arcanists so they're literate, but my primary-alt Awyrbyrt is totally illiterate. It's mostly played up for laughs because nobody seems to realize it, or acknowledge it, IC (say he's walking through the deep Twelveswood with a party and they pass by a sign that reads "danger"- the others take note of it but say nothing, assuming they can all read it, and Awyrbyrt just looks at it and goes "oh a sign" and keeps moving) He might eventually learn to read but for now he's being a stubborn arse about it, despite his father's insistence.
My other illiterate character is reserved for private RP but she grew up an orphan in deep La Noscea so she had absolutely no reason nor resources to learn. In the setting she usually finds herself in it's not really relevant.
Most of my characters are arcanists so they're literate, but my primary-alt Awyrbyrt is totally illiterate. It's mostly played up for laughs because nobody seems to realize it, or acknowledge it, IC (say he's walking through the deep Twelveswood with a party and they pass by a sign that reads "danger"- the others take note of it but say nothing, assuming they can all read it, and Awyrbyrt just looks at it and goes "oh a sign" and keeps moving) He might eventually learn to read but for now he's being a stubborn arse about it, despite his father's insistence.
My other illiterate character is reserved for private RP but she grew up an orphan in deep La Noscea so she had absolutely no reason nor resources to learn. In the setting she usually finds herself in it's not really relevant.