And do we know that looking at the result cited ? ( i doubt you need to be at 100% all or most of the time for something your render queue not being empty immediately at least one time when a new frame is ready during a multi minute benchmark).It's actually very easy to determine how GPU limited you are. You just monitor your GPU utilization. It's either hitting 100% GPU utilization or it's not. It's not rocket science.
you can look at how different the fps of an 7800x3d at 1080p can be between a 4090 and a 7900xtx and how it change title to title in which direction it is faster, I doubt we would see the 4090 being at 100% usage when it is slower on it, maxing out his wattage necessarily, more caused by driver overhead.