Up until now, they made every change fit well to the lore.
Like when the monsters grew bigger and all the NPCs noticed and wondered about the reason.
Or this whole 7th catastrophe thing which will alter how Eorzea looks completely.

But I really want to see how they will do THIS now, because it changes so many things in such an extreme way..
Just implementing it without explanation -> extremely bad.
Saying stuff like "Oh, we sent the fire, ice and thunder elementals to Ul'dah so they can help the Thaumaturges"..->still very bad.
And please explain to me why a class which is so proud of being able to fight without weapons NOR magic now becomes magic based..monk..this does not even fit the Final Fantasy definition of MONK anymore, and certainly not the FFXIV definition.
I bet it's going to just be thrown at us without making sense.
Instead of writing "These changes are subject to change." under the new class system,
they should have written in the beginning "The lore of this game is subject to change, so don't expect a nice story which makes any sense at all."