At the very least, manufacturers should be required to make their android build files available, even if they are kept in an escrow until the manufacturer stops selling that model (or they go out of business). Most of the phones going to the dump are because no updates are available, even though the hardware is still fine and any individual person (with a little patience) could build the latest release if they had the hardware bin files available.
For what it’s worth, that’s the goal behind GKI (generic kernel image)
It allows Google to update the phone without the manufacturer’s input
Would that also be available to individuals, or is something that only Google would have access to? There’s at least a couple groups actively keeping maintained images available for various phones. I keep thinking I want to try one but never get around to it before the phone is fully in use.
It should make it somewhat easier for individuals as well
The idea is that you have the vendor image with Qualcomm or Samsung specific drivers, and you can build AOSP for everything else
The structs in the kernel have some extra GKI space so if they change, it can still support the older drivers
The downside is Google is planning on pushing the updates through the Play Store, so it will take some effort to make it work in AOSP for Lineage/Graphene, etc
