Lot of effort has gone into that video, but the guy possibly haven't tried a lot of headphones or not well versed with audio and how it's described objectively.
This is a slightly older video but little more useful.
Type Springloft Studio in YouTube and watch the entire series. Sadly the guy has probably passed away...he made some really good videos with audio samples ( those were so nicely recorded even YouTube compression couldn't completely destroy them)
But you will possibly cry after seeing the videos in that channel...another nice human being gone too soon