Just a followup for people looking for convergence right now, I've tried many of the projects (all of which are good in their own ways) and the one that seems farthest along on being both a phone and a regular Linux computer is Fedora. You get a choice on login whether you want to use GNOME shell or phosh. Attached is my Pinephone CE running LibreOffice Writer.
No disrespect to UBPorts, which seems to have the best "phone" ecosystem.
No disrespect to UBPorts, which seems to have the best "phone" ecosystem.