>>34717>why bother keeping that AOSP at all and not just build a new, like postmarket or Pure OS?
You talking about pure linux os without android? This would be failure, as it happened before.
There are two main points:
1) Users need apps. Nowadays every service has an app, sometimes it has app and no real web interface even - so you are forced to use app. And, of course, apps are made only for ios and android, maybe sometimes for some kind of winphone, but it is dead. So, if you want to use phone daily as main device, you need some kind of android support.
2) Even with all flaws, android is somewhat polished. It has every needed basic service (email, messages, calls, vpns) and consistent guy. If you go into linux, you'll hardly find any good apps and interfaces that will work on mobile as average user want. Imagine using thunderbird on small touchscreen? Of course there are projects like nemo mobile, plasma mobile and such, but they aren't completely usable for average user anyway.
I've had Jolla as main phone for almost 5 years. These Finnish guys truly tried to make usable phone for average person, yet it was still usable only for person who is ok to use featureless broken thing for ideological purpose. They had classic linux inside (only non-typical thing was custom wayland compositor for guy), no problems with root, shells etc, scripting, pretty beautiful and interesing UI based on gestures. But their apps were still bad, for example, mail client was clumsy, jabber had no conference support, SIP wasn't supported, copy function between apps sometimes didn't work etc.
They also had some kind of android emulation service (alien dalvik) that allowed to run android apps in some kind of separate space. It worked, and sometimes even saved the situation when you really need that app but there is no native substitution (and never be, like whatsapp that bans unofficial clients). But it didn't support google play and had limit on API support (4.1 on first Jolla phone), so only some apps worked. Now they changed it to 8.0, but, as far as I can see, there are plenty of compatibility bugs (like non-working sound in some apps).
Sometimes daily usage was struggle, but in general it was ok. But I'm that user that doesn't care much about social networks etc, and I could ignore some apps that everyone have. For more common user, Jolla wouldn't be usable.
Then, when phone died, I've bought typical android phone (because new jollas are software-only packs for sony phones, filled with bugs). I still miss Jolla UI and full linux inside, but as product, android is much better - everything works as intended, no bugs (compared to Jolla), everything is supported.
It is very hard to create usable OS for everyone that wouldn't be based on android nowadays. It requires very large amount of investments and manpower.