"I hate that this Final Fantasy game has fantasy and worldbuilding in it."
Seriously. XIII asked you to remember, like, 4 terms, and two of them were nearly the same, and they get beaten into your skull over the initial hours of the story.
It's not even like they're incredibly alien, abstract concepts, either.
Fal'cie are physical gods. L'cie are their often involuntary thralls. Cie'th are "damned" L'cie who've failed their Focus, that being a quest given to them by their Fal'Cie master.
Boom. Done. It's SUPER fucking straightforward, honestly. It's just pretty standard fantasy tropes and concepts with a new set of titled applied.
How is it any different from any other series having a fictional language, or naming fictional races?
It's such a "bitching for the sake of bitching" argument and I can only assume that the people I hear it from don't have the attention span for a large RPG, anyway.
Pretty much exactly how I feel. I've seen people complain about L'Cie and Fal'Cie but then rattle on about asari, turians, witchers, dragonborn, etc. RPGs have a lot of words and names that are nonsense without context.