I agree, but that doesn't make it any less valuable of a metric. Nvidia cards are extremely widespread, reporting the performance on Nvidia hardware does a good job of representing what a lot of people will experience.
Furthermore, Nvidia made inroads for Wayland support years ago, GNOME just refused to adopt it. Nvidia's terms were always that Wayland implimentations could adopt EGLstreams whenever they wanted, and that GBM would not be considered an acceptable alternative until it was faster. Their so-called hostility towards the Linux desktop mostly amounts to not contributing to GNOME and making their drivers proprietary for so long. In that sense, they're about as evil as webkit contributors who don't fix x86-linux bugs.
That whole GBM debacle was simply their masking of a deeper problem. They can't interoperate with the kernel properly because their driver module is not GPL compliant. And proper Wayland support relies on a lot of kernel (DRM) functionality. They have to do convoluted dance workarounds to address the above.
Basically, Nvidia will never work really well on Wayland until their kernel driver is upstreamed. This year they finally decided to open source their kernel module. But it's still some road for them to get to upstreaming.
Furthermore, Nvidia made inroads for Wayland support years ago, GNOME just refused to adopt it. Nvidia's terms were always that Wayland implimentations could adopt EGLstreams whenever they wanted, and that GBM would not be considered an acceptable alternative until it was faster. Their so-called hostility towards the Linux desktop mostly amounts to not contributing to GNOME and making their drivers proprietary for so long. In that sense, they're about as evil as webkit contributors who don't fix x86-linux bugs.