This isn’t ethnic, it’s cultural.
I agree 100%. But hosepipe isn’t proposing retaliatory violence against a cultural group, he’s recommending it against an ethnic group.
To be fair, there’s a great deal of overlap between cultural and ethnic groups in this case. Not all members of the ethny are participants in the culture, and the culture incorporates people who are not part of the ethny. But the correlation is pretty high between the two.
And I’m not the one who defined members of the ethny who don’t follow the cultural norms as “acting white.”