In this hypothetical situation, a programmer masquerades as a trade expert in order to share an important message with the newscaster: stop incorrectly using the word “backslash” when you mean “forward slash” (a common error).
There is no actual humor in this comic strip, as it merely serves to point out something that the reader will vehemently agree with. Through a clever psychological trick, the Author is able to use this strong agreement to simulate enjoyment and reverence. This same tactic is used by many major news networks, such as Fox News.