If the Chinese guy got changed then he probably wasn't interviewed as our guy was. After all the Chinese won a fair few medals! Their journalists probably weren't too bothered at that stage!
I can't believe I'm posting to defend this....Seriously! He'll be remembered for what he achieved not what he wore for goodness sake!
maybe they took this one step further - made multiple clones of the athletes and switched them to improve performance - they may have had one clone per round, so the guy who fought the first round had plenty of time to change.
As his fight was the second last in the entire Olympics and just before start of opening ceremony, they had to present the medals a few minutes after the fight so there was no time for him to change into tracksuit. The bronze medal winners got their medals a day or two after they last fought - after the gold/silver bouts, so they were not in boxing gear when they were getting their medals.