It's not their first rodeo. Their cards already need to authenticate with the driver to enable the card completely. When I last checked, Nouveau driver has received a key which only enabled the hardware, allowing enough features to see a desktop and install closed NVIDIA drivers, nothing more.

Remember, the kernel module is open source, but rest of the driver is closed source, and any kernel level code which can't be open sourced but had to be is moved to card firmware. Only the kernel module is open source. Not the libraries, not the driver, nothing else.

NVIDIA is holding to its pearls like a sloth holding to its branch, because their all business model and livelihood is dependent on that control. I still commend AMD's decision to allow full card enablement with any driver which talks the correct language.