Now given THAT context, I can agree that it would've been nice to have it that way. Sort of like FFXIII paradigms that assign you a name given what you have equipped spells and equipment -wise.
However, given what they're trying to achieve in the current context, the job system they have in place with the addition of hopefully more than one job per class (i'll be pretty gutted if they dont add more down the line), it just makes more sense. They want a system that's reminiscent of previous FF's, so that's what we're getting.
Edit: Thinking about it, it would've been nice to have something like IX's system where you learn abilities from individual weapon and armour use. So you could equip a certain shield and learn defender after using it for a while, equip another higher level one a bit later and maybe learn phalanx. You could equip an axe and eventually learn beast killer.
The only problem with this system would be that everyone would end up using the same stuff, similar to what we have now ingame. It would be hard to balance encounters unless these 'titles' you earned came with specific buffs. Like equipping the stuff to turn you into a paladinw ould also grant a defence boost, enmity boost, cure potency etc.