The NVidia driver is 535.247.01, at least according to nvidia-smi
Like I said, there are a bunch of udev rules that disable Wayland on gdm:
$ sudo cat /usr/lib/udev/rules.d/61-gdm.rules
SUBSYSTEM!="pci", GOTO="gdm_pci_device_end"
ACTION!="bind", ACTION!="add", GOTO="gdm_pci_device_end"
# cirrus
ATTR{vendor}=="0x1013", ATTR{device}=="0x00b8", ATTR{subsystem_vendor}=="0x1af4", ATTR{subsystem_device}=="0x1100", RUN+="/usr/bin/touch /run/udev/gdm-machine-has-virtual-gpu", ENV{GDM_MACHINE_HAS_VIRTUAL_GPU}="1", GOTO="gdm_pci_device_end"
# virtio
ATTR{vendor}=="0x1af4", ATTR{device}=="0x1050", ATTR{subsystem_vendor}=="0x1af4", ATTR{subsystem_device}=="0x1100", RUN+="/usr/bin/touch /run/udev/gdm-machine-has-virtual-gpu", ENV{GDM_MACHINE_HAS_VIRTUAL_GPU}="1", GOTO="gdm_pci_device_end"
# qxl
ATTR{vendor}=="0x1b36", ATTR{device}=="0x0100", RUN+="/usr/bin/touch /run/udev/gdm-machine-has-virtual-gpu", ENV{GDM_MACHINE_HAS_VIRTUAL_GPU}="1", GOTO="gdm_pci_device_end"
# vga
ATTR{vendor}=="0x1234", ATTR{device}=="0x1111", RUN+="/usr/bin/touch /run/udev/gdm-machine-has-virtual-gpu", ENV{GDM_MACHINE_HAS_VIRTUAL_GPU}="1", GOTO="gdm_pci_device_end"
# disable Wayland on Hi1710 chipsets
ATTR{vendor}=="0x19e5", ATTR{device}=="0x1711", GOTO="gdm_disable_wayland"
LABEL="gdm_pci_device_end"
# If this machine has a hardware GPU, take note
KERNEL!="card[0-9]*", GOTO="gdm_hardware_gpu_end"
KERNEL=="card[0-9]-*", GOTO="gdm_hardware_gpu_end"
SUBSYSTEM!="drm", GOTO="gdm_hardware_gpu_end"
DRIVERS=="simple-framebuffer", GOTO="gdm_hardware_gpu_end"
IMPORT{parent}="GDM_MACHINE_HAS_VIRTUAL_GPU"
ENV{GDM_MACHINE_HAS_VIRTUAL_GPU}!="1", RUN+="/usr/bin/touch /run/udev/gdm-machine-has-hardware-gpu"
LABEL="gdm_hardware_gpu_end"
# The vendor nvidia driver has multiple modules that need to be loaded before GDM can make an
# informed choice on which way to proceed, so force GDM to wait until NVidia's modules are
# loaded before starting up.
KERNEL!="nvidia", GOTO="gdm_nvidia_end"
SUBSYSTEM!="module", GOTO="gdm_nvidia_end"
ACTION!="add", GOTO="gdm_nvidia_end"
RUN+="/usr/bin/touch /run/udev/gdm-machine-has-vendor-nvidia-driver"
# Import nvidia kernel parameters
IMPORT{program}="/bin/sh -c \"sed -e 's/: /=/g' -e 's/\([^[:upper:]]\)\([[:upper:]]\)/\1_\2/g' -e 's/[[:lower:]]/\U&/g' -e 's/^/NVIDIA_/' /proc/driver/nvidia/params\""
# Check if S0ix-based power management is available
# If it is, there's no need to check for the suspend/resume services
ENV{NVIDIA_ENABLE_S0IX_POWER_MANAGEMENT}=="1", GOTO="gdm_nvidia_suspend_end"
# Check if suspend/resume services necessary for working wayland support is available
TEST{0711}!="/usr/bin/nvidia-sleep.sh", GOTO="gdm_disable_wayland"
TEST{0711}!="/usr/lib/systemd/system-sleep/nvidia", GOTO="gdm_disable_wayland"
ENV{NVIDIA_PRESERVE_VIDEO_MEMORY_ALLOCATIONS}!="1", GOTO="gdm_disable_wayland"
IMPORT{program}="/bin/sh -c 'echo NVIDIA_HIBERNATE=`systemctl is-enabled nvidia-hibernate`'"
ENV{NVIDIA_HIBERNATE}!="enabled", GOTO="gdm_disable_wayland"
IMPORT{program}="/bin/sh -c 'echo NVIDIA_RESUME=`systemctl is-enabled nvidia-resume`'"
ENV{NVIDIA_RESUME}!="enabled", GOTO="gdm_disable_wayland"
IMPORT{program}="/bin/sh -c 'echo NVIDIA_SUSPEND=`systemctl is-enabled nvidia-suspend`'"
ENV{NVIDIA_SUSPEND}!="enabled", GOTO="gdm_disable_wayland"
LABEL="gdm_nvidia_suspend_end"
LABEL="gdm_nvidia_end"
# If this is a hybrid graphics setup, take note
KERNEL!="card[1-9]*", GOTO="gdm_hybrid_graphics_check_end"
KERNEL=="card[1-9]-*", GOTO="gdm_hybrid_graphics_check_end"
SUBSYSTEM!="drm", GOTO="gdm_hybrid_graphics_check_end"
ACTION!="add", GOTO="gdm_hybrid_graphics_check_end"
IMPORT{program}="/bin/sh -c \"echo GDM_NUMBER_OF_GRAPHICS_CARDS=`ls -1d /sys/class/drm/card[0-9] | wc -l`\""
ENV{GDM_NUMBER_OF_GRAPHICS_CARDS}=="1", RUN+="/usr/bin/rm -f /run/udev/gdm-machine-has-hybrid-graphics"
ENV{GDM_NUMBER_OF_GRAPHICS_CARDS}!="1", RUN+="/usr/bin/touch /run/udev/gdm-machine-has-hybrid-graphics"
LABEL="gdm_hybrid_graphics_check_end"
# Disable wayland in situation where we're in a guest with a virtual gpu and host passthrough gpu
#LABEL="gdm_virt_passthrough_check"
TEST!="/run/udev/gdm-machine-has-hybrid-graphics", GOTO="gdm_virt_passthrough_check_end"
TEST!="/run/udev/gdm-machine-has-virtual-gpu", GOTO="gdm_virt_passthrough_check_end"
TEST!="/run/udev/gdm-machine-has-hardware-gpu", GOTO="gdm_virt_passthrough_check_end"
GOTO="gdm_disable_wayland"
LABEL="gdm_virt_passthrough_check_end"
# Disable wayland when there are multiple virtual gpus
#LABEL="gdm_virt_multi_gpu_check"
TEST!="/run/udev/gdm-machine-has-hybrid-graphics", GOTO="gdm_virt_multi_gpu_check_end"
TEST!="/run/udev/gdm-machine-has-virtual-gpu", GOTO="gdm_virt_multi_gpu_check_end"
TEST=="/run/udev/gdm-machine-has-hardware-gpu", GOTO="gdm_virt_multi_gpu_check_end"
LABEL="gdm_virt_multi_gpu_check_end"
GOTO="gdm_end"
LABEL="gdm_disable_wayland"
RUN+="/usr/libexec/gdm-runtime-config set daemon WaylandEnable false"
GOTO="gdm_end"
LABEL="gdm_end"
One of those is a hybrid GPU system. I thought those were created by the gdm developers and not Debian. In any case these rules do disable Wayland Gnome but if you turn them off then gdm does not start.