A non-profit collective of device manufacturers and software developers could probably create a very effective and potent steward for Android's long-term development. But I wouldn't hold my breath.
Kinda, yeah. I mean Android is already Linux, just with suspicious, proprietary drivers that hold it back. Some Android phones are still running kernel 3!
If manufacturers would just upstream their drivers and make them less shit, then android could take advantage of the entire body of work in GNU/Linux userland.
I can imagine manufacturers that are fully in the Android ecosystem come together to maintain Android, including Xiaomi, Samsung, Oppo etc. There won't be as many feature updates, but it's not like Google puts a lot of resources in Android, or Android is delivering many features these days -- Google moved/laid off many people on Android teams, and many of the recent updates are very minor features. Just look at what's new in Android 14 or 15 -- barely anything. I stopped getting excited about or even caring about major version updates for a while. The pace has already slowed down quite a bit compared to a decade ago, and the ecosystem is very mature and stable.