It seems like you're getting some kind of racial McGurk effect here? Kelly Rowland does not talk anything like this in the linked video. Here is what she actually says:
"Here's the sitch. I don't know what that is. I don't know what Microsoft Excel is. I don't know. I don't have a clue. So when I saw all these memes, I was like 'I don't care'."
Apart from 'sitch' and 'like' (which are both very common usages in informal conversation) this is all fully standard American English. You're getting worked up about someone saying that (i) they don't know what Microsoft Excel is and (ii) that they don't care about some memes. The "performative idiocy" exists only in your imagination.
The irony is that you're doing your own version of performative idiocy in your attempt to (I guess?) imitate Black American English.