AKA: He's Not Exactly Captain America Here
Since the death of the Conspiracy, The X-Files' overarching plot has lacked a certain sense of urgency. It's not that the series actual stakes have gone anywhere, the invasion is still theoretically impending. But without the human players working in and around that, those stakes have never seemed more nebulous, and I think the series knows it. They needed a new hook to build their Myth Arc episodes around, and with only a little bit of digging, they found one.