By no means do I intend to white knight CoD here, but one of the main advantages perceivable there is that any progression is essentially horizontal. Leveling gives more options, to increase the complexity of how you interact versus other options equipped by other players. You already start off with basically balanced classes from the start. It's less about instant gratification in terms of rewards, etc., as it is about instant action, immediately getting to a position where you can see where you really stand, with a full range of interaction within that environment (your class vs. any other, even if you do not yet have access to every class). The same can be said for mobas like HotS, DotA2, LoL, or FPS-objective games like Overwatch or TF2, or just about any other arena skill-based game. Seems a little bit weird then to be putting that example in line with a vertical progression model like XIV's, where unranked PvP (luckily there at least) is one of the few places where gear doesn't especially matter. They're fundamentally different, especially when so little of XIV, and most notably while leveling, depends on skill far more than gear.
Now, in the sense that a model was proven to work and then gets milked into a dry husk of a corpse, sure, XIV does certainly follow that idea, along with the majority of MMOs released since WoW's success to some degree or another. And like most, they forget that WoW worked as well as WoW did back then because it was WoW, and not especially due to its model.
To be honest, I almost wish that instantgratificationaction was the case with XIV. I don't mean that in the sense of wanting to be level 60 immediately (it didn't even take especially long to get all combat jobs to 60 as is), but simply that I'd like to be challenged, at appropriate escalation, from the start. Give due support and additional intermediate content for struggling players, rather than glossing over or trimming down mechanics to avoid conflicts.
/rant