It seems that hackability of tests, along with their purpose can be generalized. Tests, like big company politics, are signalling mechanisms. The totality of all tests, culminating in a degree from an institution of a certain prestige, is a signal of potential to contribute.

Companies and other big institutions need very strong assurance that supplicants will indeed "work out" by comporting themselves to the culture and making valuable contributions to their goals. And the reason such absurdly strong signals of assurance are needed is the ridiculous level of friction inherent in admission to and ejection from these institutions and their hierarchy of stations.

So, to get into Big Company X, you need a prestigious degree, and to advance once you're there, you must identify and play their internal signalling games. Such is the attachment to signalling, that you'd often do much better to lead the holiday decoration committee than to create actual value by solving some important problem.

The relative lack of friction in open source is why, given the ability and inclination, even a dog can contribute at a high level.