An attention-grabbing title, no? One can take the phrase, insert their noun of choice for "x", and instantly imply that they can impart special knowledge to an audience eager to learn the heretofore unknown errors of their ways.
It seems reasonable to assume that the claim is intentionally outlandish. A presentation to a room of business experts won't be taken seriously if everything they know about business is wrong, and the presenter naturally needs to utilize the audience's existing knowledge set to propose a convincing counter-theory.
Most people implicitly accept that not everything they think will actually be overturned when they absorb content stemming from such a jarring headline, but they also want to know what the creator thinks is so important to be considered revolutionary in their field. The absolute nature of the claim sets the bar high for the claimant relative to his compatriots; expectations are high in those who call the bluff and take up the challenge to listen.
The contender puts his reputation on the line when the time comes to justify the contention. The challenge is in striking a balance between the commonly-accepted pool of knowledge and the new approaches to the information being postulated. A talk consisting entirely of novel data, unverified observations, and radical suggestions is naturally difficult to believe and will likely be ridiculed even if the conclusions are relevant and useful. Conversely, a talk consisting largely of well-known discussions and culminating simply in a different interpretative conclusion of the same knowledge set is underwhelming, and the audience may leave disappointed given the initial claim.
The court of public opinion ultimately determines the success of the presenter's ideas, but the final verdict isn't always obvious in the short-term. Einstein didn't posit his work on relativity with the hook "Everything You Know About Time is Wrong", but to an extent such usage could now be considered an appropriate challenge to 20th century physicists.
For illustrative purposes, I will also point out that my own attempt at using the idiom, "Everything You've Ever Thought Is Stupid", was not received well.