Why all the criticism when it's only PRELIMINARIES? When the team and individual competitions come up, there will be plenty of opportunity to see gymnasts from the other countries.
As Berthe's Ghost pointed out on another Olympics thread, she watched the BBC program on men's swimming and all the commentators talked about were the British swimmers, neither of whom won a medal. The medalwinners were completely ignored! Be realistic. ANY country's telecast is going to focus mainly on athletes from that country. Why should US networks NOT focus on US athletes?