Android shouldn't be considered Open Source anymore, since source code is published in batches and only part of the system is open, with more and more apps going behind the Google ecosystem itself.
Maybe it's time for a third large phone OS, whether it comes from China getting fed up with the US and Google's shenanigans (Huawei has HarmonyOS but it's not open) or some "GNU/Linux" touch version that has a serious ecosystem. Especially when more and more apps and services are "mobile-first" or "mobile-only" like banking.
That is a very hard problem, unless someone with serious name recognition like Linus Torvalds starts to lead that kind of effort, or a big company like Microsoft suddenly decides that putting 1 billion towards GNU/Linux would be in their interest. With small efforts, it will remain scattered.
Crowdfunding has a lot of power if there is name recognition behind the effort. Star Citizen has already gathered $800 million with mostly enthusiasm and a good start. Who is there to lead the effort for GNU/Linux phone development?
Linus is a kernel hacker, and already busy tending to his own project.
"GNU/Linux" is effectively a committee of communities, with sometimes conflicting goals. It took Canonical and Valve to put things into shape on the desktop, and that's mostly because desktop was becoming less relevant.
I see two ways for things to change here:
- A massive, for-profit corporation, someone willing and able to challenge Google and Apple on an even ground, is hell-bent on making a Linux-based phone (Microsoft failed even after acquiring Nokia);
- Another platform shift happens, making smartphones irrelevant in comparison (think: when smartphones displaced desktops).