Those same quibbles applied to the policy before the addition of the LLM section: how does the NetBSD project detect if I copy & paste a bunch of code from my day job into a patch submission (and then lie about it)? Obviously, they can't. I, personally, don't feel like it's a failure of the policy if it relies on your contributors acting in good faith, because:
a) many people are acting in good faith, and their behavior will change as a result of this policy;
b) if someone wants to be a jerk and use an LLM after they were told not to, and is at some later time found out, it makes it easier for the org to act quickly and in a fair and consistent manner;
c) [more speculative as to the motives of the NetBSD project] normative statements by well-regarded institutions are useful in setting an example for other organizations to follow, so there is some political utility regardless of the practical efficacy of these rules.
a) many people are acting in good faith, and their behavior will change as a result of this policy;
b) if someone wants to be a jerk and use an LLM after they were told not to, and is at some later time found out, it makes it easier for the org to act quickly and in a fair and consistent manner;
c) [more speculative as to the motives of the NetBSD project] normative statements by well-regarded institutions are useful in setting an example for other organizations to follow, so there is some political utility regardless of the practical efficacy of these rules.