I don't think there should have been a reason for any of these discoveries to be mind-boggling. It's the premise that we knew anything before we knew, e.g. religious indoctrination that made it so. Would the confirmation of aliens be mind-boggling today? For some yes, why?

But on the sheer vastness of what we didn't know, it seems like that's shrinking in relevance. There are of course dark areas, black holes, quantum gravity, and so on, but they are farther and farther at the edges of scale. Not as world-changing as discovering the second island after your own, or a continent, planet, or solar system. Each one has less practical impact.