It will help. It won't fix the problem by any means.

It is, like in most of the other games FFXIV has faithfully copied, an inherent problem with allowing ease of leveling solo. You don't have to learn to play well because you can happily level up mostly solo except where forced to group, and then they hit end game not really knowing how to play worth anything. WoW, Rift, TOR, GW2, all of them have this problem, primarily because they provide a difficulty curve during the leveling process that ranges from flat to a very gentle slope.

Bringing dungeon exp up would help. But not very much. In all of those games, chaining dungeon runs was by far better experience than leveling solo, but an overwhelming portion of the playerbase did it solo anyway because easymode is what they're after. That's fine until you crank the difficulty up right at the end and suddenly end up with a ton of subpar players who can't pull their weight because they never learned how.