And with Buffy's new found enthusiasm for being a Slayer comes new found motivation for Giles, who spent all of last season as something of a hanger-on.
The key elements, ancient astronauts and the Stargate’s coordinates, were in the movie and were fully exploited in a way that was consistent with the events in Stargate.
I would love to say that Season Four worked as a metaphor for the transition we all make the year after we graduate from high school, but it simply wasn't good enough.