On the verge? No. XIII's sales are some of the best for a Console RPG in years. However, it's hard to deny that the franchise is being weakened. 13 and 14, especially the latter, were probably the critically worst received entries in main series history, and in a world where console games are increasingly Western style and handheld games are generally Eastern style, HD behemoth JRPGs will have trouble finding a niche.
Imagine the theoretical gamer of 2014. Why would they play Final Fantasy 15? The last game of note in the series was in 2006, 2001 if you hated XII, the last entries are hated on forums everywhere, and they got their JRPG fix on the PSP2 and 3DS. What would FF15 offer that Dragon Quest 11, Pokemon 6, and Monster Hunter 4 couldn't?
Final Fantasy is not on the verge of collapse, but it is on the road.
