I can assure you that young brits, so-called royal family or not, are just as dumb as young people everywhere can be. Harry is a product of his upbringing and his culture so as my dear mother-in-law would say "He a idiot".
It's no different than white frat boys in colleges in America, get caught wearing blackface and wearing afro wigs, and then have to make a fake apology, saying "they didn't know it was wrong to do it."
Once you get passed the visual and what it represents (as offensive as it is), The more offensive aspect of this whole incident is the theme of the party, which was suppose to be a "bad taste party" the tittle of the Party was "Natives and Colonials", it just goes to show the mentality of these people.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .