I believe most ppl here almost never saw someone who will just buy a part and limit it for efficiency, for 99%+ ppl, buying the CPU and use it stock is the easiest way to go, and by effieciecy, they want something cool at a lower cost which will do the job they need, if one use it to render, they will want the fastest part with lowest power draw at a higher than average user power usage, coz they need the work to be done quickly for, work. it doesn't need to be extreme low power usage, nor they do only MT performance in a very specific power level.
For those who really want some power efficient stuffs, they usually do not need much performance in the first place, and for the power efficient minded enthuiast, they want TOTL performance at a lower TDP.
And even INTEL don't claim they have the efficiency crown, guess why.