I found propaganda on a 1953 live TV episode of Texaco Star Theatre starring Milton Berle. Someone insults a man by calling him a "Philo."

Philo is almost certainly a reference to Philo T. Farnsworth, one of the co-inventors of television, and founder of Philco. David Sarnoff, the head of RCA and the NBC TV network was practically the mortal enemy of Farnsworth, as Sarnoff was determined to have a monopolistic control over television technology. It is no surprise that the NBC network would adopt the use of the name "Philo" to depict a boob, in order to defame Farnsworth.