Gotta agree with Syntaxlies. FFXI thrived off of the sense of achievement you got just by leveling up enough to wear that cool looking piece of gear you always saw people in when you were low level. FFXIV isn't FFXI, but it's fair to say that in many ways they do share a niche, and this kind of thing would kind of destroy that a bit. Appearance is an important motivating factor and the exclusivity of various looks so to speak contributes to gameplay and fun as weird as that sounds. It's kind of an often overlooked reward of leveling up.