This is a digram made to better understand and get an overview of kubernetes security. It's not complete (but you are welcome to submitt a PR), nor is it perfect, it is biased and it might not be for you.
It might however help you to discuss kubernetes in a security-context with your team, or just to get a better understanding yourself.
The drawing is most likely an overkill. It is not ment as a "solution" or design. Also, it is on-prem... For non on-prem, it might not be that relevant.
It is made for the purpose stated above inside Telenor Norway. It doesn't reflect any internal designs, architecture or even pattern. The diagram was made for discussion, but ended up being a good cheatsheet in general. So it's released so other companies or people might use it as well.