Notebookcheck always isolates CPU power by measuring idle and draw from the wall.

Many top quality CPU reviewers also do this. Chinese reviewer Geekerwan is probably the best at it. In the past, written reviews like Anandtech will always do it. Today, anyone with video editing software thinks they can review CPU performance.

Ever since Youtube, there have been plenty of low quality reviewers that mislead people. I didn’t know who this Jeff guy was but now he’s on my list as one. There are still some who do proper reviews.