Ok… forget about this post. I just made it all work perfectly by removing: optimus-manager, gdm-prime, libgdm-prime. And later following the proper tutorial from [HowTo] Use Wayland with proprietary NVIDIA drivers
Previously, I’ve seen tutorials quite similar to this one, but missing the instruction “2) To force-enable Wayland…”, which seems to be critical. Without it, my system would boot, but it wouldn’t open GDM and I would be stuck to the console.