The thing is, the FMV opening movies are not actually made by the FFXIV development team, but by a specialist team in SE called Square Enix Visual Works, and it takes at least a year or more to produce just one of those openings. SE Visual Works also is responsible for FMV production for other titles so no wonder it's use here in FFXIV is limited.

Graphics have come a long way from the FFVII days when it was actually used as a means of hiding loading screens for pre-rendered backgrounds so cutscenes that would have been handled with pre-rendered FMV previously are now depicted with in-game graphics and models - so-called 'real-time video'. Sure it might not have the fanciness of FMV but at least it allows the player's own character to be depicted in the scene rather than a boilerplate stand-in like 'Derplander'.