Is there something wrong there? We (NumPy) would love to get feedback and improve it.
This would be a natural “next step” https://numpy.org/devdocs/user/theory.broadcasting.html
It never hurts to have several sources explaining the same concepts. It's like course books, they usually have different ways to explain the same concepts and focus on different aspects. Different people prefer different styles and sometimes you have to combine multiple sources to get a good understanding of the concepts that are being explained. I don't think that it's an indication that there's anything wrong with the source.
Since you asked for feedback though, on my laptop half the page is taken up by menus on the right and left side. It would be nice if those parts could be hidden so that you only see the content. I could do that by using reader view in my browser but that removes the layout and the images, which is kind of important here.