I wonder why it is so difficult to update from Android 4 to higher versions. My old desktop computer worked well with Win XP, but also worked / works without problems with Win Vista, Win 7, Win 8, Win 10. Ok, I changed the version from 32 bit to 64 bit, but still, it works. It even works, if I just install Win 10 from the DVD without internet connection (then it just installs some “basic” MS drivers). At least most of the 32 bit drivers are compatible, if they worked with Vista (there was a change in driver architecture between XP and Vista; one reason that I support the ReactOS project).
Now, I don’t know anything about the android driver architecture. Are there huge differences between the versions? Why is it not possible to just update the android by keeping the old hardware drivers?