So in the US, the joke is “I’m 10% Cherokee princess”, which is just a blonde white girls way of excusing their own racism when it inevitably falls out of their dumpster of a mouth.

I can usually disarm it with “yeah I’m half Japanese and half American, I can’t tell which side I hate the most”

I’m wondering if that Irish-German-Russian-Scottish is a similar “wise coverage” play? I don’t know, just guessing.