My point is the escape prevention is necessary. By the end of the video the kid is no longer in fight or flight crisis mode. You can see he is no longer panicking. That's the point of exposure therapy. Would a controlled systematic desensitization be more effective? Of course.

That said, the goal shouldn't be to make it stress free. That is the problem in the first place. The anxiety avoidance cycle is based entirely on the avoidance of stress/anxiety. Making the process entirely stress free only negatively reinforces the person's avoidance of stress inducing situations. Many behavioral psychologists argue that relaxation training and graded exposure that is especially slow in the systematic desensitization process may actually do just that (strengthen the anxiety avoidance response).

Others have pointed out that it was just one chicken, not an army of them. So this is actually a graded exposure that really was pretty effective, I bet (making an assumption here about what happens the next time the kid encounters a similar experience).

I think future confidence in the presence of chickens is more likely than trauma, in this case.