This clipping describes racially and ethnically (and other) seperate graduations at UCLA. My own university indulges the same.
Around the world, seperatists are killing each other. Name a conflict and the odds are overwhelming that it is over some ancient blood-grudge.
And we in America still do better assimilation than most other countries.
These two factoids are more than enough for me to suggest that universities not indulge these graduations. If people want to celebrate with their own selection of friends after the ceremonies, great and that's their choice.
Housing and employment laws discourage racial separation. And the same people that back these laws lack the spine to nix graduation racism.