It's actually more of a running gag. Everyone knows there are several people posting anonymously, one of whom is Karen. At some point, it was decided that all trolls would be referred to as "Karen," both to reflect the consistencies of their viewpoints and to cause the "Karens" to constantly deny the postings. "It wasn't me, it was another anon..." etc. That's all.
Nobody takes it seriously, nor does anyone believe it's one person, but it's amusing to watch them get all riled up. It's reflective of the "programs" in that they (the Karens, like the the program kids) all get treated the same way and get "consequences" as a group, whether the consequences apply to the particular individual or not. It's just funny to watch them react exactly as the kids react under the same treatment. It shows the programs create the problem, they don't treat it.
Anyway, that's my take on it.