Interesting video but I disagree with what his main argument is. He's saying that pushing the bottleneck to the GPU would mean you're not really testing the CPU fully. True but that isn't really relevant. He also says that if you were to test a GTX 1060 and GTX 1080 at 720p where the bottleneck is in the CPU, you'd get similar results and conclude that the cards are the same speed. Well yes...that's the point. At 720p there is no point in buying a GTX 1080 over a GTX 1060. Likewise, if you're in a situation where the CPU isn't a bottleneck then there's no point buying a more expensive Intel CPU over Ryzen.worth watching the Gamers Nexus video just posted - entitled "Explaining Ryzen Review Differences (Again)" - goes into gaming performance as well as other things
The fact that you want your CPU to last longer than your GPU is a fair point so you don't want bottlenecks down the line. However, games aren't going to prefer fewer cores in the future, are they?