I mean that’s true - if you only mean Ignis’ premonition. The scenes that happen during the end credits though take place after the time skip (which is in itself a spoiler even with the distant prologue of the Ifrit fight) and really do spoil things thematically, with Noctis talking about his resolve. I guess ideally someone should play Episode Noctis after chapter 9 but not watch the credits, and then watch the credits again after beating the main game.