Did they? I cant find a total number of sales but apparently FF16 sold 3 million copies in a week while being an exclusive. IIRC the game met square expectations so it was by no means a commercial failure.Persona 5 has 7 million, Undertale has 7 million on Steam, and Three Houses has 4 million as an exclusive. FFXVI might eventually surpass TH but probably not before it stops being an exclusive and it does not seem like the type of game to have strong legs like them.