Comment by jeroenhd
The "fix" would be to make games perform like shit on Windows and disable HDR and other proprietary features, or to abolish the open Linux drivers. You can't have both, unless you do what Nvidia does and move all of the proprietary stuff to the GPU firmware and write a minimal driver to control that massive firmware blob. Which, obviously, would require reengineering the GPU hardware, which is expensive and of questionable value.
They can't open source their proprietary drivers even if they wanted to because they don't own all of the IP and their code is full of NDA'd trade secrets. AMD isn't paying two different teams to do the same work because they like wasting money.
AMD already has large firmware blobs. Both intel and nvidia have the software side of GPUs figured out.