A coworker of mine formerly worked on Nvidia's proprietary drivers. They remarked at just how wrong the Nouveau driver was about certain things, including the functionality and reasons for certain registers.
I wish I'd had more conversational courage at the time to "stand up" for nouveau with them; it was super rude to shit on someone else's hard work, especially when the reason why they had to do that hard work was because nvidia was a bunch of jerks with a shitty FOSS policy.
Presumably RedHat are in the same boat.