The only one that really had an actual spoiler though was the Heavensward opening - ARR's one was just the End of an Era/New Beginning trailer, and Stormblood's one the spoilers were only minor and wouldn't have even been obvious. And Shadowbringers opening is purely symbolic and not a true rendition of the expansion's narrative (several scenes took place before the expansion's time period, and other things shown never even happen at all). So really only the HW one was an actual spoiler, the others were more just showing off things to come without being outright spoilers.