Personalization is a well-established driver of student engagement, yet delivering individualized instruction at scale remains a challenge in online education. Recent advances in generative AI make scalable personalization feasible, but AI-generated educational videos are often perceived as inferior to human-recorded content. This tension raises the question: how does the value of personalization compare to that of human presence? We investigated this question through a field deployment in two offerings of a large undergraduate online course (493 respondents). AI-generated personalized videos served as the primary instructional modality, alongside a smaller set of non-personalized human-recorded and AI-generated videos. At the end of the course, students ranked preferences across personalized and non-personalized formats and human-recorded versus AI-generated content. In a direct comparison, students preferred AI-generated personalized videos over human-recorded non-personalized videos (mean rank 2.26 vs. 2.69; Wilcoxon signed-rank test, ).
