> readymade set of sacraments and oaths one can apply to any business to achieve magical effects
On the contrary, MBAs are designed not to be a "management formula" but teach by experience in two ways: first, exposure to thousands of real life case studies (often, in the better programs, with the CEO who lived it participating in the class discussion), and a class formed of carefully balanced profiles to have a mix of experiences contributing to the class discussion.
Domain experts will of course judge what they know: the accounting classes are weak, the investment classes are outdated, etc. but I'd argue there is no better way to speed-teach a generalist exposure, because the real world is complicated and management is about juggling inadequate resources and conflicting objectives for which there are often no rules. Whatever "rules" are taught (such as accounting standards, or using EBITDA instead of revenue for company valuation) are the product of generations of trial and error and tend to exist for a reason; it's good to question the rule and look up the reason, part of building a better mental model of how the world works.
Look at Enron: today, the black and white story is that they were fraudsters, but if you dig into the history of the company, first there were tons of genuinely interesting and moral people employed there because they believed in the vision and second there was a pattern of "the end justifies the means" from the true believers in management. So when you see a ton of smart people hired by true believers taking ethical shortcuts because "the end justifies the means"...
The generalist part is important. You might think you do not need to know about accounting or legal issues now, but as a manager they will come up. Just being aware of what can go wrong (reducing unknown unknowns) can go a long way in mitigating temptation. I think this is missed by many people who are on a certain career track: for example, I often hear that the CFA is better than an MBA if you want to stay in finance, and this may well be true (disclaimer: bailed out after failing level 2) but the CFA won't teach you, for example, how to deal with a toxic C-level hire, nor will you hear first hand a former infantry officer describe instances of creative leadership under intense pressure. Anecdotally, this kind of experience comes in a handy in private equity whilst being less useful in global macro trading.
Philip Delves Boughton's book [1] in particular captures this quite well.
[1] https://www.amazon.com/Ahead-Curve-Harvard-Business-School/d...