Not allowing students to insult, bully or terrorize other students due to their skin colour doesn't seem to be an "official ideology".
Except that's not at all what happened. If somebody gets recorded in private saying they hate <insert group here> that doesn't, or at least shouldn't, constitute bullying, insulting, or threatening.
And, anyways, in Europe, that wouldn't be the question, the question would be "Should prosecutor file charges for heinous speech against those students?".
But that's freaking stupid, and is nothing to be proud of. You can have freedom of speech, not "freedom of speech except.....".
If you have the latter then you don't really have freedom of speech at all, just freedom of popular speech.