[fastball]

I'm the cofounder of a startup[1] working on an app that might scratch your itch.

We built a note-taking system around digital notecards instead of documents, and those cards can be both linked hierarchally with parent/child relationships (and unlike most other platforms a card can have multiple parents) as well as with inline markdown link-style linking that you'll find in many other apps / wikis / tools for thought.

I definitely think the notecard format could be very useful for this use-case, as one card = one argument makes a lot of sense.

[1] https://supernotes.app