If the title simply said "AI is out-performing humans at CTF" then none of this confusion exists. Nothing is "broken," we don't need to be superfluous with "frontier," and the point is still there.
But the article is arguing it is broken. That’s the point. You can disagree but that’s very much that the author is writing about, not a curiosity, and that it’s these top models that are not custom security models.
It's like "Forklifts outperform humans in weightlifting". The problem, of course, is that a forklift is much easier to spot among athletes than an AI among CTF players.