Maybe the content was removed because of the X360 port, but it seems to me that it's for the better anyway. Hearing what the content that was cut was going to be -- a zoo? seriously? -- I'd say that SE overdeveloped before I'd say that the 360 held it back.
Dedicated FF fans wouldn't mind an FF that was longer than 100 hours, but the average RPG player likely does not want a game with more than 50-70 hours of story and directed gameplay. XV would be out before anyone could even get to the end of XIII.