The e.foundation home page caters to users without any technical knowledge, which is great but I'm not sure users of alternative mobile operating systems are quite there yet. It's not even immediately obvious this is Android-based.
It would be useful to list some more specifics. Is this built on LineageOS? Does it come with their own cloud services? Can you opt out of that? How close do you track LineageOS?
The video shows someone installing the Facebook app. That puts a limit to how de-googled this could possibly be. How are those products distributed? Can anything from the Play store be installed the same way?
Happy user of LineageOS here, but there is definitively room for a more complete system with best of breed open source apps installed for those services most people require (mail, chat, maps etc.). Alternative application stores makes me wary however, F-Droid does an admirable job but compared to something like Debian they are still tiny.