In fact, a combination of the two is likely to be even more effective. As another commenter mentioned, heuristic-based analysis can generate false positives, but that's less of a problem if it's possible to analyze these in an additional AI step.

Also worth pointing out that the N isn't too terribly large: the article says that the ecosystem has about 4000 plugins and themes? With that volume, you could almost reasonably just use static analysis to flag suspicious plugins (saving tokens), have an AI do a pre-analysis and pass to a human for final decision-making.