Nvidia actually DOES have good OpenGL drivers that are unfortunately proprietary. AMD GPU drivers have been getting progressively better to where they represent a valid alternative for gaming. Intel GPU drivers have long been good enough for general use.
I think the principal is that if Google had licensed Fuchsia in such a way as to require release of source code to kernel modules that companies would rightly fear being sued for violating the copyright of a mega corp like google in a way that GPL violators don't fear say the free software foundation.
The year is 2027 and you have in your hand the 2025 model of the Samsung Galaxy Note 17 and you really wish you could run some snappy new version of the OS Samsung released for the galaxy note 19 but even though hardware wise they are really quite similar there is something in the proprietary bits that just doesn't seem to work but lacking the source you are forced to give up.
You wonder if you can install a new android or other Linux based OS can be installed on your hardware unfortunately no gpu drivers exist for Linux so again you are forced to give up. The only software you can run is the official software from your OEM. In theory the OS you run is open source but if anyone who isn't a major OEM builds an alternative version it works as expected without proprietary bits and binaries signed by the manufacturer your device wont talk to your email provider, your bank, netflix, spotify. Instead of free as in beer or free as in libre its free as in bullcrap.
The point is without the onus being on OEMs to provide source for their drivers people have only as many options as OEM's opt to give them.
