What is bullshit is the attempt to appropriate a useful neutral adjective to mean more than it does. Mathy is just mathy. Physics is more mathy than psychology. Too mathy can be bad, sure.
I see it as attempting to provide a patina of quantifiability for an essentially qualitative or incalculable result. If it is actually used as a measure, then it will lead to horrible distortion. The "next article" on the site is about OKRs (objectives and key results) and how they can be used to motivate and also destroy motivation, inspire and also make people afraid, by how faithfully you stick to the measurement and how much you assume the Os and KRs are actually tied to business results. The example of the Virginia Mason Quality Equation is somewhat egregious because it is presented as an equation but nothing in it is properly quantifiable, the units are meaningless, and the authors say it's not to be calculated.
However, there is value in putting everything in a mnemonic so that you remember its parts, and what adds and subtracts from the results. Amazon shipping and FedEx Express have different types of quality. Amazon is next-day or better for virtually everything and unreliable. It comes with a guarantee to refund the cost of shipping, which is 0 in most cases. FedEx Express has varying service levels at increasing costs for performance and includes meaninful guarantees and insurance tied to the performance goal. If Amazon fails to deliver on time, it is frustrating but probably not typically enough to make the user quit using the service or attempt to sue, as they didn't pay for specific service and they are satisfied with the overall expediency of the service. If FedEx Express had Amazon levels of performance, they would lose to competitors who are willing to provide the requested service, regardless of whether they refund people's delivery charges. Putting it back in the equation, the Appropriateness of the service dominates the difference between Amazon Shipping and FedEx Express, where Amazon can tolerate more bad outcomes in their model and FedEx can tolerate more waste (higher fees). Amazon can impress you with same-day delivery you didn't ask for while FedEx has no need to do so, people want merely on-time delivery at the price level they requested.
In the past century Psychology transformed from speculative writing combined with clinical observation, to sophisticated statistical analysis and attempt to follow scientific methods, because many audiences including yourself believe that makes it more true.
https://en.m.wikipedia.org/wiki/Truthiness
H/t Colbert.