Yes, we've started from scratch. A detailed explanation for our reasoning can be found here:

https://marcoapp.io/blog/marco-an-introduction

TLDR: There are _no_ IMAP-primitive truly cross-platform email clients in existence, except for Missive, which is built for team collaboration. We are building something net new.

The content on the website is indeed a minimal representation and the actual alpha product has matured quite a bit beyond what you see there.

The kanban suggestion is brilliant, I have made a note of that.