Durant hasn't had a chance to win an Olympic gold medal. LeBron is 1 for 2.
Here's the thing people sometimes forget. After Team USA failed in the 2004 Olympics, they had another chance to redeem themselves before the 2008 Olympics. In 2006, Team USA could have redeemed themselves. This time, LeBron and Wade and Carmelo were the leaders of the team. LeBron had already established himself as a superstar in the league, after his third NBA season, just like Durant this summer. Wade just got done winning a championship and a Finals MVP. Their team had more talent than this Team USA. They once again won bronze.
So trying to discredit what Durant did in these FIBA World championships is futile and frankly silly. LeBron + Wade + Carmelo couldn't do it in 2006. And Durant had far less help on this team.