Comment by microtonal

What's better for privacy, an old but inexpensive smartphone running Android 11, or the same smartphone running an up-to-date third-party rebuild of Android 16 or newer

I see your point, but it would be very misleading, since the phone would still have a lot of known holes. Only the OS would get updated, typically not the drivers, driver firmware, possibly not the kernel. The phone would still be easily compromised through all the known RCEs. So you tie up non-profit projects in a lot of extra work to get an improvement that does not really matter.

This is a mess created by the OEMs and they will continue to create this mess until people will stop buying from OEMs that only give lip service to security updates (roll out Android Security Bulletins to show a high patch level, while in reality the phone the phone has many known CVEs).