As far as I can understand, AMD has released the specs for the new GPUs, which is what many Linux / Open Source advocates care about, right? Sure they haven't yet added the support for the new cards on their own, but other people could do it if they are in a hurry, right? Then you have Nvidia not releasing any specs for open drivers, but adding support (more quickly perhaps?) on their proprietary binary drivers. This upsets (hopefully a different set of) Linux users.
And in the end, this is just about games (because I never had a problem with the Linux desktop in general, even over multiple displays with mostly AMD cards), right? Well, guess what, Linux is not a good gaming platform. It is great in many things, why should it also be good for games? Why would Nvidia and AMD spend significant resources so that very few people (compared to the total market) can play games in a specific platform that, let's face it, is not gamer-oriented? Well, they don't, so don't complain. Sorry for the rant-ish post, perhaps I would post different 15 years ago when I was still into computer games