@Fleppensteijn @leopold @stevecrox
All of Wayland is based on EGL. What you are referring to are EGLStreams vs GBM which are both libraries using EGL. Nvidia drivers now support GBM for all supported GPUs via a support library that comes with the driver (libnvidia-egl-gbm https://download.nvidia.com/XFree86/Linux-x86_64/510.39.01/README/gbm.html). There should be no difference in the GPU generation used.
@Fleppensteijn @leopold @stevecrox
For troubleshooting, I recommend
For trouble shooting recommend https://community.kde.org/Plasma/Wayland/Nvidia, checking whether all kwin backends are installed (kwin-wayland-backend-* on Ubuntu). Sometimes there's also a problem with the missing OpenGL backends of Qt. An easy check to see whether there is a problem with the proprietary driver is to try out whether the problem also exists using nouveau.