The West has a tendency to cherry pick techniques from holistic approaches (for example quick path to mindfulness vs meditation and Buddhism). I suppose it's a cultural difference. In my opinion, it is really worth it to try to understand Lean as a whole instead of looking at kanban only.
I agree that it's worth it to spend some time to understand the holistic approach... but there's also a lot of bullshit and over-reliance on form over function.
The “bullshit” emphasis on form before function is a pretty standard part of a 3 stage learning method - naive and unquestioning memorization of rules/form, unique combinations of the memorized forms, and finally throwing it all out the window and inventing new forms with the newly acquired knowledge and skills.