Good lectures are phenomenally useful, far better than individual unguided review of the material. They're often IME very interactive too.

STEM subjects are particularly hard to create good lectures for. And STEM expertise and speaking/communication skills don't always overlap either.

The non-STEM classes I learned the most in are the ones I learned the most in lecture in. The STEM classes, on the other hand, were pretty scattershot without as much correlation.

An LLM-based toolset could likely be much better than that and at least as good as bad lectures, but the guardrails are gonna need to be really really really good.