That guy doesn’t look healthy at all and looks older than I bet he actually is.
Sugar is addictive and the individual in the video, like any other addict, will promote his addiction to justify it.
Further, and this is backed up with many meta studies, lack of healthy animal fats affects brain performance. You’ll get first hand proof of that with a forthcoming comment from a soon to be posted comment I’m certain(protecting the name of the forthcoming guilty party out of charity)