Hi there -
It is not GPU bound. Actually GPU time is lower than game thread. NVIDIA Reflex is disabled, and same with other NVIDIA settings that could apply here as I’ve seen other say similarly to you that these can be a cause.
Although I suspect you are right and there is some driver issue at play as it seems to happen only on some hardware and not others.
Same issue is again reported here by others also:
They find the same, that is shows up on NVDA but not AMD GPUs.