Check out the https://ubports.com/ project, they have continued Ubuntu Phone (which has officially been discontinued), and they have made really impressive progress since then. You can really run it on a phone and have all drivers working, unlike postmarketOS (but we have different goals, remember).

One of our goals is packaging all sorts of user interfaces, and ubports is one of them (but it depends on individual developers, if they actually want to do it, because developers are encouraged to work on what they like most): https://github.com/postmarketOS/pmbootstrap/issues/62