Final Fantasy iOS game shuts down over unfixable bug

Guessing it's likely due to Apple's approval process. You can try to patch 1 major issue but they won't approve an update unless it also adds compatibility for all of their new standards and features.

Not to say that's unreasonable of Apple, but if the game's not making money on that platform anymore I can understand the decision to just pull it rather than sink more resources into supporting it in perpetuity.

Plus it's just not a good remaster anyways, they really bungled up the multiplayer capability. I don't think anything of value has been lost.