This is a core pitch of How to Take Smart Notes and Evergreen notes.
If you do your knowledge work as a web of evergreen notes, then areas where you have a natural concentration of notes will have enough material to write a piece about.
Look for clusters in your notes, you can likely assemble these notes into a larger piece. At this point, you already have your first draft when you sit down to write.
Now you can just edit this series of thoughts into a publishable piece.
This builds on Knowledge work should accrete over time.
If you Create speculative outlines while you write and link evergreen notes as you write them, you can start to slowly build up pieces you want to write about over time. This gives structure to the accretion.