>What we can surmise is that Nvidia refused to collaborate

I saw more effort on Nvidia's side trying to collaborate than on the Wayland side. I think it's unfair to not call out the people who had a hardline stance of only caring about open source drivers and didn't want to do the work to onboard Nvidia.

I think you’re significantly retconning what happened.

Mesa did discuss EGL but felt it wasn’t the right choice. https://mesa-dev.freedesktop.narkive.com/qq4iQ7RR/egl-stream...

In much the same way that NVIDIA may have felt that EGL was the better choice.

However none of your description of the way things are explains why NVIDIA couldn’t have made their own libgbm that matched the symbols of mesa and worked on standardizing the api by de facto.