Not individually but as a function of society. These people keep standards high, even the ones who are unreasonable. I don’t like them and I would hate to deal with them but in contrast they make reasonable people appear reasonable. If there were no Karen’s you might get attitude for asking for a clean spoon. So have some appreciation for these horrible people.
I don’t want people to be kept in check because they fear being slapped, and I don’t believe most people become their better selves through experiencing or fearing pain. So no, I don’t see Karens as presenting a solution to the problem of managing poor behavior.
That being said, what I do think is a problem for the Karen term is that insults are invariably misused in ways that hurt innocent parties. The women who are inconveniently or inarticulately but legitimately angry have reason to fear being mislabeled by those who want to shove them into a mental box and out of sight.