Probably for the best. I don't think they'll ever top that initial season for genuine surprise/fun/nostalgia. Get in, get out, before it all becomes a tired, stayed-around-too-long punchline and shell of its former self.
I wish more things - movie franchises, TV shows, athletes, musicians, teachers/professors, elected officials/politicians, etc. - would grasp this concept.
Leave folks wanting more,
not asking "WTF is this still doing here?!"