I face the exact same dilemma in my field of interest - time management. The fact is, most authors and content creators focus their advice at the beginner-level for several reasons...it's easy to explain, applies to a mass audience, and sells better.

But they themselves don't read beginner-level stuff. They hire coaches, and eventually learn how to diagnose their own performance at an expert level. Think of Lewis Hamilton, Tom Brady or Serena Williams.

But this lesson isn't shared widely, although it is ubiquitous across arenas of high achievement which are well-defined.

Here is an article I wrote describing The Shift that learners need to make to continue growing. https://medium.com/2time-labs/3-ways-to-improve-your-task-management-as-a-system-vs-a-collection-9d7fbc2666c7