Somehow I only noticed this now, six-months after its release –> Automattic, the makers of WordPress, run their company on a flavor of Knotable.
It’s a theme for their own product called P2 –> https://theme.wordpress.com/themes/p2-breathe/
Try it or look at it.
Feature for feature: it’s Knotable. A way to make notes, edit them in real time, and comment, etc etc.
They run their company on it — a global, all remote team with no meetings or voice calls.