I’ve listened to some YouTube videos that recap TV shows and that sort of thing. Sometimes they phrase events as “this would happen”. Maybe I’m wrong but to me that phrasing implies either a) it happened frequently b) it was planned to happen or c) it happened at a point in the story we’re not at yet. But sometimes I hear that phrasing used when it doesn’t mean any of those things. Sometimes I hear the narrator shift back and forth from “this happened” to “this would happen” and back to “this happened” while recounting events in chronological order. It just sounds to me like “this would happen” should be used when jumping ahead slightly and briefly mentioning something that will happen later in the timeline, but that isn’t how it’s being used.