My 5 cents, the value of KA is that it gives you some sort of basic curriculum you can follow. To finish calculus (the "basic", single variable) I've had to pull in lots of other books, youtube channels, courses from other universities, but it still has it's worth. It's like a rope bridge over a high river.

Major weaknesses are some cool sections like Linear Algebra that have no exercises in their respective "tree", but that's very rare.