I did a fairly rigorous linear algebra course in school, and it went over my head despite passing it.

Saw it explained in a single slide of Andrew Ng's ML course and everything clicked perfectly.

Where I lived math was taught like fucking shit, it was all algebra and zero context as to why it could be useful in real-life scenarios, zero abstraction such as visualization or metaphor. Everyone involved in concocting that pedagogic aberration should feel terrible about it.

The Coursera one? That's the exact course I was thinking of.

Which class?

A sibling comment to your mentioned Andrew Ng's class, and I actually had the same experience as them with the same class. You can find it by searching for Stanford CS229; the lectures are available on YouTube.

It was Andrew Ng's machine learning class on Coursera