Game design should be expected to minimize the probability of catastrophic failure, not completely abdicate responsibility for this and dump the entire job on the GM, who has enough work to do already. For example, it's not supposed to be the GM's job to try and balance effects of using charms on the fly because the charms are broken as fuck on paper. That is the game developer's job, to build stuff that players can buy without the GM having to worry that pushing the button labeled Breathing on the Black Mirror will break the game, bringing the session screeching to a halt and wasting time with a table argument.
The GM has a limited amount of processing power, attention, patience and time in the game session. Limited resources that should be allocated towards doing the stuff that only the human GM can do, like play NPCs, cause events to occur, cause the setting to react to the players' actions, and so on. From the GM's perspective, a well-designed game does as much work for them as possible: the mechanics should be balanced, the settings should work for whatever the game is trying to do, the players' build choices should be fair and lacking in landmines and spike traps, etc, etc, so as to free up resources to do what only the GM can do. You, the GM, should be able to trust the product you have bought to do this work, else why buy it as opposed to rollin' your own?
To use an analogy, a well-built car cannot stop someone determined to drive off a cliff, but it can and will reduce the likelihood of accidents, and if any occur, raise your probability of survival. A piece of crap built out of scrap and held together with string might be able to drive, but you don't have a rollcage, nor airbags, nor power braking, and your fuel tank is open and exposed to the elements. Which is more likely to have an accident?
Is "anyone can drive off a cliff if they're trying to do so and there's no way to stop them, so we won't bother building car safety features into our vehicles!" a good argument with respect to cars? Should "put fuel, move forward, everything else is the driver's problem" be the principle an engineer cares about when constructing this machine?
