While the nuances of nationality, regions, and so forth might point to the NHL's diversity, most people see two groups on the ice: white guys and white guys with beards.
Meanwhile, basketball has been a city game since shortly after its inception. Once dominated by Jews and immigrants, it gave away to Black Fives like the Harlem Globetrotters and, not too long after, black superstars like Oscar Robertson, Bill Russell, Wilt Chamberlain and Elgin Baylor. The NBA had the first black head coach, the first black general manager, the first black owner and the first black majority owner. Its sidelines have long had the most diverse presence, with black coaches sometimes accounting for more than a third of the league's head men.
Under David Stern's leadership and the 1992 Dream Team's example, the game expanded globally at a much higher rate. Today, the game is represented by players from all six inhabited continents with participation expanding literally all over the world. Given the limited cost of courts, equipment and participation, the game could one day rival soccer in terms of ubiquity and popularity. In the NHL, diversity has grown as the sport has expanded throughout Europe and, significantly, hockey-playing countries and regions have grown more diverse. The NHL has also been active in constructing facilities and creating instructional programs in urban areas. The day is very near that, on average, there will be a black player on every professional team.
In addition to the increased number of black players, their roles and origins have also varied more widely. Fan favorites like P.K. Subban, Wayne Simmonds, and Evander Kane lead a new generation of black NHL'ers. Subban also has two younger brothers, goalie Malcolm who projects as a first-round pick, and defenseman Jordan, who may be the most talented of the trio. Still, the NHL has a long way to go until it achieves the multicultural reach of the NBA, and that's a significant hindrance to its ultimate appeal.