Where exactly is the value here?

I struggle to believe there can be any 'tech' that can't be rapidly copied in a note taking app (correct me if I'm wrong)

And it's not _that_ well known either so it's not like they're buying into a massive mainstream thing.

I don't get it.

There are already free / free-ish clones of Roam:

  * org-roam: https://github.com/org-roam/org-roam
  * Obsidian: https://obsidian.md/
  * Athens: https://github.com/athensresearch/athens