I thought we already did get xp boosts in game...
The Armory XP Bonus
The Brand New Ring +30% XP bonus
The various +XP earrings we've seen over the years
Food Buff XP bonuses.
Also I'm fairly certain you can't level a character from 1 to 120 in 4 hours no matter what buffs or methods you use in WoW.
While I know some may not agree with me, I feel that the main focus of FFXIV IS the story and those who want to skip it without ever engaging with it (as opposed to rolling an alt after doing the story with a main) aren't really the people FFXIV is designed for.
If someone is "new" to FFXIV I feel they should need to experience the story IMO. They should not be able to skip it because the story IS the game. The paid story skip is for those foolish enough, in my opinion, to actually pay to not play the game. Those who feel the need to rush to max lvl through the most expedient method possible so they can just jump into endgame content are not, in my opinion, the audience the game is primarily designed for, and anyone coming into FFXIV with such a mindset is going to have a very bad time I think. More so, when such a player actually does reach max level and finds the endgame, such as it is, isn't what they were expecting, and doesn't fit what they think an endgame should be. Then they blame FFXIV for not being more like WoW. FFXIV is not WoW and it's not trying to be.
I play both FFXIV and WoW concurrently and I like both for different reasons. I enjoy my time in FFXIV because it typically doesn't share the same things that frustrate me about wow (FFXIV has a whole different list of things to frustrate me :P )