I haven't watched the documentary, but I assume you're familiar with the impact of behaviorism on the advertising industry, before WW2?

John B. Watson[0] (founder of the behavioural psychology school) pivoted to advertising in the beginning of the 20th century.

For those who are not familiar with the subject or his research methods, I recommend reading up on the Little Albert experiment[1].

[0] https://en.wikipedia.org/wiki/John_B._Watson [1] https://en.wikipedia.org/wiki/Little_Albert_experiment