BEIJING — The NHL decision to pull out of the 2022 Winter Olympics allowed a crop of prospects and some overseas vets to represent their countries. For the United States, the dropoff in talent didn't matter much in the opening game against China. The Americans rolled to a 8-0 victory — seven of those goals coming in the last two periods — on Thursday at National Indoor Stadium to start group play. Then again, it's worth considering the opponent. China — only fielding a team at these Winter Olympics because it is the host nation — is ranked 32nd in…