Oh, I'm not that it exists but the assertion was that the use of "oreo" was pervasive - I'm not convinced of that given thadisputingt I've never heard anyone use that term in real life.
For what it's worth, my ex-girlfriend (an African fugee) was called an oreo (among other things) by African Americans who didn't approve of her lifestyle.
Again, it exists, but if in 38 years of growing up black, going to school with blacks, living, working, playing sports, dating, etc with blacks, I've never heard it, and I don't know anyone who has heard it, I really can't consider it "pervasive".
Lots of things exist, but aren't pervasive - terrorism for example.
I don't know that "Oreo" is a pervasive slur. I've certainly never heard it IRL.