I wouldn't place it in the uncanny valley. It just sounds highly scripted and acted.

I think the videos serve as an introduction to some basic concepts intended to bring some clarity for further in-depth study. The video is much like the "front matter" to a chapter in a book.

Of course, the _REAL_ learning work starts when the student suffers through countless problems and proofs. This is no replacement for that. One doesn't learn math by passively watching videos or listening to lectures. That's the way it is and that is the way it will always be. This just provides a clear 30,000 foot view of the topic, a little motivation and background and, yes, some eye candy (and that's OK too).

The presenter is an actress. It's effectively a monologue.

I saw the same thing... it was like she was trying to give sexy looks while also teaching me math. Rather distracting. Did you also notice that?