Re: Preposterous
Yup.
I had a similar experience both with an off-brand android tablet and an Samsumg Note 8.
I was able to get a different firmware (LiniageOS) on both, but the off brand tablet ran slower than molasses on a cold winter's day, and a bunch of stuff on the Note 8 didn't work, because Samsung decided (in their infinite wisdom) to not contribute drivers for things like the audio subsystem to the overall ecosystem. (we'll ignore the pen input for the moment, but it was also not present)
Samsung has a track record of providing 18 months worth of updates to their devices period- after that, even if it's a security issue that ranks a 12 on the CVSS scale*, you are SOL by and large, and your only real choice is to get a different device, even if the hardware is still functional.
Shame really, the Note 8 was pretty decent hardware and the pen input was very useful for doodling with.