The video is interesting because of the extreme reaction of the family cat when he smells the local stray cat on his owner’s fingers. It’s just the smell and immediately the family cat wants to attack and such is his hatred that he will even attack his owner’s hand. It is a bit sad that domestic cats can be so driven by this sort of aggression. It is unnecessary. I realize that statement is meaningless as cats react instinctively but under these circumstances there is no need for this untrammelled aggression.
Jackson Galaxy did a show on a similar situation. Maybe he can help.