@thomaskuntzz @forgefed I do suspect though, that there's some underlying problem about the email approach.
Some people say email is perfect for this job, and the only missing part is good UI. And they may be right.
But I wonder, why no such UI exists, despite the long time email has been around. And I wonder, what if the problem is that on the bottom line, computers exist to serve us, and we people simply want convenient UIs that are easy to use and communicate well with us. And advanced devs tend to use advanced tools whose UIs don't work for the general population, such as the Mutt email client... and having all their tech knowledge, they can't see anymore, why people keep preferring shiny web UIs over email.
It's really simple, folks. It's because typing plain text into a textbox is way, way less friendly than dedicated buttons and widgets. The plain text stuff requires the user to do more technical thinking.
For email to compete with ActivityPub on UI, ML servers / MUAs would need to start having UI for interacting with the variety of possible email attachment file media types...