It's not just energy, chip surface is still a thing. Performance core designs will jump at almost any opportunity to go faster. 50% more transistors to get 5% m

It's not just energy, chip surface is still a thing. Performance core designs will jump at almost any opportunity to go faster. 50% more transistors to get 5% more single thread performance? What are you waiting for, do it! But when it comes to highly parallelizaable loads spending the transistor budget on more cores of slightly lower performance will certainly be better.