Man, that video was embarrassing. Both teams just keep pitifully serving into the net. The umpire calls them to the center of the court to tell them to knock-it-off ... and they start back up almost immediately.
The rules of this sport are obviously screwy ... but, from that video, they were enough of an embarrassment to justify bouncing them.
SnakeDoc
The trouble is not the rules of the sport, but the competition format instituted for the Olympics, namely round robin Group Play.
Under a single elimination format, this would never happen.
But under Group Play, top tier teams, who are almost guaranteed to advance to the next round, gain a competitive advantage in next round by avoiding other top teams due to "seeding".