"I made one prompted comment about them on Australian radio"
That means she was specifically asked about the Kardashians. It's not like she brought them up just because.
No but she has brought them up in countless interviews since. I remember reading another article like this not too long ago about her commenting about the family.
I really don't see how this became a thing. She didn't attack them personally and she didn't say anything that hasn't been said since 2009.
And I don't get how that Oprah comment fits. Why would O comment on something Rebel said? Rebel said they don't have talent, not that they don't work or keep busy as it were.