I think it's not just due to budget constraints, it feels like a creative vision problem as well.
I've been thinking about it lately but for being a video game XIV takes little advantage of it's own medium.
The story and gameplay are often very disconnected, or I guess segmented into their own little pockets.
An overwhelming majority of quests are just you going to a place to talk to a guy, reading text boxes, before he sends you off to do the same thing again somewhere else, broken up by the occasional "go there and kill two enemies" quest or a dungeon.
The rare solo instance, and I guess variant dungeons to an extent, is the only time where the storytelling is integrated into the actual gameplay portion of the game.