I am not convinced that this is better ('hand drawn diagrams'). We've been drawing diagrams of all kinds for a very long time with no hurdles whatsoever [1]. Millions of diagrams have been drawn by boring-big-corp orgs in PowerPoint. This just reads like a hipster fetish over aesthetics, not substance. And if we're talking about aesthetics, I much prefer Monodraw [2]. I have a bias for having appeal for boring things may be because it works and gets out of the way. Emojis in your readme? No thanks.
That said, the app itself has great UX, especially onboarding. Just straight to drawing mode. Kind of like autodraw.io.
[1] https://commons.wikimedia.org/wiki/File:Arpanet_logical_map,...