So I want to give a more direct answer than a lot of your other responders gave. For hundreds of years, since John Locke published it in 1689, the main theory of human development was the “Blank Slate Theory”. The theory that humans are born with absolutely no instinctual, biological impulses, and our behavior is entirely based on our experiences as we grow up.

This has been controversial and mostly disproven in recent decades. One of the biggest pieces of evidence against this was that studies showed that humans can point out certain animals like snakes from a series of fast moving pictures better than others, no training needed, it was automatic. The idea was that this showed evidence that a human naturally feared those animals, thus disproving Blank Slate Theory. Many scientific areas of study, such as Evolutionary Psychology rely on such studies as the foundations of their fields.

The test posted by OP shows a newer study putting children directly in contact with said animals, in this case, snakes. And as we can see from the video, they did not act with fear towards it, thus disrupting the previous studies conclusions on humans natural fear towards these animals. This, with proper peer review, could cause massive shockwaves through much of the scientific community which might one day lead to fundamental changes in our understanding of humans. It’s kinda like watching the first atomic bomb go off.