Ofcourse, those drivers are still curated by Apple. Back in 2004, Apple flirted with the idea of opening up Software Update for third parties, but has since decided against it.
"The computer company fears that third party developers could accidently release buggy or infected software updates, which would ultimately effect the Mac OS X operating system, causing customers to fault Apple."
Btw thanks for including links!
Maybe the feature could be added as an opt-in for the user. This is what ubuntu does - https://help.ubuntu.com/community/Repositories/Ubuntu#Adding... , works great.
Also the fact that random regular company can actually host their own apt repo and ask their users to add it to their apt configuration and then receive updates via the System Updater is kind of neat. There are several companies which do this - cloudera being among one of them, virtualbox being another.