The above NPR, states that a Karen is a new label, started in the 2010s (which is just last year, even). It also shows how the Karen label is different from other, prior labels.
It delineates how a Becky is different, a "Miss Ann" is different.
We've historically had labels like this for people, which are racially linked. But this is 2020, this is a NEW label, and other NEW labels keep popping up.
We need to collectively STOP this. No more racist, sexist, ageist, anything-ist labels. It's all wrong.
(Not saying you were defending label use... just clarifying my position)
Slurs are not new. And as I mentioned, what you showed were not Karens, but 'white women who act poorly in certain ways'.
"Kaben" has unique connotations, a specific meaning. While I agree that "white women have had slurs" before 'Karen', I'm going to have to disagree that it's germane here.
0. https://www.npr.org/2020/07/14/891177904/whats-in-a-karen