> Nothing is upstreamed because the quality is so shoddy that you'd get Linus Torvalds into a proper ragepost if you dared to post it for submission

True, but the community does clean up and upstream stuff over time. It's just very slow work, made even more confusing by how much SoC hardware components are duplicated with small variations in different platforms. De-duplicating and merging drivers for some random IP block can involve pretty serious effort