I noticed this problem with the NVIDIA proprietary driver on each and every upgrade of Ubuntu versions. Can I remove the prop driver and manage with the generic open source driver?
This solution was initially posted by the OP as a part of the question.
To remove the NVIDIA drivers completely
sudo apt purge ^nvidia
Some of the additional components which may raise issue need to be removed
sudo apt purge bumblebee vdpauinfo vulkan-utils
The removed and the pending dependencies can be fixed by installing the Ubuntu Desktop
sudo apt install ubuntu-desktop
In some versions of Ubuntu the xorg config will create some issue so it needs to be removed. If not found it will be well and good.
sudo rm /etc/X11/xorg.conf
Now make nouveau the default driver
echo 'nouveau' | sudo tee -a /etc/modules
If nouveau was blacklisted it is advisable to remove the blacklist
sudo rm /etc/modprobe.d/blacklist-nouveau.conf
This the last and the final step of the process
sudo update-initramfs -k all -u
Reboot the computer and check the brightness controls and the video playback.