The video does not say olive oil is the best bike chain lubricant nor does it recommend it as such. In fact, it refers to it as "amusing", states that no information on real world performance was provided, and it was something to remember if you have a dry chain while you are out having lunch somewhere (apparently tongue in cheek). It cites one study that found that it was very efficient in short-term reduction of friction. While the reduction of friction is important, it is only one facet of what makes a lubricant practical and effective. The high lubricity only lasts while the olive oil stays wet. Olive and other vegetable oils break down quickly and will soon become gummy and rancid attracting grit. Try it, I'll bet you will have to reapply it every hour or so of riding and will have a sticky mess in short order.

There have been some successful "bio" lubricants produced, but they are highly refined and chemically modified soy or other oils that are designed for continuous wet applications such as transmissions or hydraulic systems. After the stabilizers and other additives are taken into account, these plant based lubricants are no more environmentally friendly or less toxic than mineral oil or synthetic products and are quite expensive. Some people have used straight canola oil as a bar lubricant for chain saws but a big difference is that chain saw chains are constantly supplied with fresh lubricant with the old lubricant being worn or thrown off during use. Even then, manufacturers recommend chain cleaning and emptying the bar oil reservoir before storage when using canola or other bio oils that do not contain stabilizers and other additives.

Is extra virgin olive oil extremely slippery? Hell yeah. Is it a practical and effective lubricant for any real world application on bicycle chains? Not a chance. At best it is a novelty or emergency lubricant that will need to be cleaned off and replaced in short order. Save it for chapped lips and pasta.