Sorry for the blatant n00b question. I searched online, the FAQ etc. and didn't see what to me is an obvious question. Supporting old devices is great. In the PC world we have general linux, but on Android and some other consumer devices, solutions have been limited. There are Android forks(?) or implementations like LineageOS that run great. I've used non-Google Android since 2018.

So what is the motivation for yet another OS solution? There must be a reason for this project to go on and have so much enthusiasm.

We think computers should act in the interest of their users. For example, they should not participate in the privacy nightmare of targeted advertising, as it is directly built into the operating systems from Amazon, Apple, Google and Microsoft, as well as the apps and services recommended by them.

This is kinda FUD, right? Google-Android has a lot of privacy invasion. But there are all kinds of Android versions that are de-Googled.

My best guess right now is that it is attempting to provide a "full featured" distro for devices that run phone and tablet OSs now. So if you want a server or full coding environment on a phone, pmOS may be better suited for that than an Android "fork".