This is a critical observation. By default, for most people who have been through the modern school system, and/or worked for companies -- they're used to covering their ass and sounding smart.
The market doesn't care about cover-your-ass -- it only cares if their problems get solved and if your product is any good.
I think there is something in operating under a fearful authority that spoils people in this way — that causes them to make excuses, obfuscate, counterattack, pass the buck or shut down when confronted by a sound argument against their way of thinking.
Once someone has succumbed to the politics within a large organization, they have likely internalized these patterns of dealing with objections.