Not sure what is going on here but many of us have been having an issue with Cyberpunk 2077 and low gpu usage, you can set the graphics options etc as low as you like but the framerate hardly goes up and usage lowers.
I have had fluctuations between 80-99% and at points as low as 70% utilisation, others have had lower than this.
We have isolated it to Asus AI suite 3, Uninstalling and using the cleaner doesn't work, you have to uninstall then perform a Windows in place upgrade or clean install.
As soon as you do this the game is at full utilisation, I have tested this by imaging my machine then installing Asus AI suite 3, only launching fan xpert and back to low gpu utilisation, re-image machine without Asus software from a clean install and straight back to 99% utilisation.
Armoury Crate is not effected.
Unsure if this is an Asus or cdpr issue.
Here's one of many threads where people have solved their issues by removing AI suite and doing a Windows in place upgrade :