@lxo my impression was that GNU started w/ userland and w/ dev tools, while hardware came w/ OS and source code drivers. Maybe the userbase attracted by that (Emacs, me) isn't used to caring about the underlying system, and hardware-bundled OS replaced by Linux was uninteresting?
I would like all general-purpose s/w to be free, and also have source code for drivers. But, theoretically, wouldn't it be enough if drivers presented a standard API/ABI? GPU code can't access n/w anyway - secure.