You know, the trouble is, you're absolutely right. I _could_ have just said "I'm working on a note-taking app", but nothing about that seems particularly weird or hard.
To address the poetic waxing more directly, it's important to remember that we still don't have very good language to talk about the "primitives of knowledge work", which is why I phrased my statement the way I did. We know it almost certainly doesn't involve the concept of "notes" (at least in the way we think about right now) and calling them simply "ideas" is altogether too vague.
As far as the #roamcult is concerned, we are overwhelmingly in agreement :)