Why was Square so obsessed by the Fabula Nova Crystallis idea?

For context, when Square announced the project i was a preteen raised by Nintendo, i didn't have a PS3/PS4/PSP and i didn't have any interest in Final Fantasy.

But in the recent years when i look into what became a huge mess in developpement and hurting a lot of Square projects at the time (FF13,14 1.0, Versus 13/15 and even Kingdom Hearts 3 was put on hold). My question is, did it seems really that much of a groundbreaking idea at the time? Because i really struggle to see why Square seemed convinced it was going to be THE new thing and hyped it so much.

For those who have seen this mess in real time, were you hyped at the time? Why was Square so into it?