> I understand that manually backporting major security and system updates to "EOL" devices is too effort for what you probably see as a small number of potential users
End-of-life devices no longer receive driver and firmware updates. Porting major OS updates to them won't resolve the insecurity. GrapheneOS is for secure devices.
> my pixel 6a is unsupported
Pixel 6a is supported by GrapheneOS and will continue to be until it's end-of-life:
@digitalCalibrator You won't get decent security on a device not receiving driver/firmware updates. Pixel 6a is not end-of-life yet and is still fully supported by GrapheneOS. It's not one of the recommended devices for new purchases due to lack of recent security features and remaining support time.
The whole point of GrapheneOS is substantially improving privacy and security from the baseline. If Android included our current privacy and security features, we'd have a large set of new ones.