Final Fantasy VII came out and confirmed how to pronounce Cait Sith properly, at least within the context of the game.
On the official Twitter account for the game, Square Enix announced that the character is pronounced “Kate Sihth”, a decision that likely vindicated many of us who in 1997 didn’t know any better.
However some fans are put off by the canon pronunciation, since the name Cait Sith is borrowed from a Gaelic folklore creature. According to some fans, under the Gaelic pronunciation it ought to be pronounced as “Ket Shee”.
Not to mention, in the decades since the game’s release Japanese fans have also been using “Ket Shee” to refer to the character.
Final Fantasy VII Rebirth is set to launch sometime in winter 2023 for PlayStation 5.