AI improves a student's ability to learn. It does nothing to improve a student's motivation to learn.

Motivating students to learn is not at all a solved task. And arguably a harder one too. Even the ~2010 "Google and grit" self-teaching is enough to outperform public education - but most students don't have the motivation to pull that off in practice. They have the opportunity, but that matters little if they don't use it.