What's the point of picking a team in the Olympics if you aren't going to pick your national team? That's literally the ENTIRE point of the Olympics. Unless you're a German hockey fan and don't have a horse in the race, it's completely absurd to root against your country in an event which is specifically designed for nations to compete with one another. I could understand not caring who wins, and only caring about seeing good games. But that means that you would be just as happy to see your team win as any other. But to actively hope another team is better than your national team makes no sense to me.
Would you root against our home country's world junior team? How about your hometown high school team? Silly.