In the USA there is no doubt that Blacks excel and dominate in basketball. For every Steve Nash or Larry Bird there are 2 MIchael Jordans or Kobie Bryants. Even in the 60s and 70s when Whites were the clear majority of the population Bill Russell, Lew Alcindor (AKA Kareem Abdul Jabbar) and Wilt Chamberlain, etc. dominated the league. Most of the NBA teams were majority Black and today some are virtually all Black. And whites are not being discriminated against, they would love to find White stars for the game, the fans are mainly White. When you go to a game the funny thing is the scalpers are all Black, the fans are largely white and the players are largely Black.
The Americans have been doing poorly in international competition lately and I am not sure why that is. College basketball stars used to win the Olympics until 1992 when they started to allow NBA players to compete. Perhaps the Europeans have gotten better, perhaps the international rules are more favorable to foreign players, I just don't know.