Some fraction of your transistors MUST go unused on average or you melt the silicon. This was already a thing in the 20nm days and I'm sure it has only gotten worse. 100% TDP utilization might correspond to 60% device utilization.
That's true for CPUs. Does it really apply to GPUs and other accelerators for embarrassingly parallel problems where going slower but wider is always a valid option?
Some fraction of your transistors MUST go unused on average or you melt the silicon. This was already a thing in the 20nm days and I'm sure it has only gotten worse. 100% TDP utilization might correspond to 60% device utilization.