I have no problem with alternative derivations of quantum theory—if they are correct! But the framework in this paper is too weak to qualify. Look at their definition of ‘category 3a’ models. They are sort of suggesting that quantum mechanics is the appropriate prediction calculus or framework for reasoning, for anything matching that description.
But in fact category 3a also includes scenarios which are completely classical. At best, they have defined a class of prediction calculi which includes quantum mechanics as a special case, but then go on to claim that this definition is the whole story about QM.
I have no problem with alternative derivations of quantum theory—if they are correct! But the framework in this paper is too weak to qualify. Look at their definition of ‘category 3a’ models. They are sort of suggesting that quantum mechanics is the appropriate prediction calculus or framework for reasoning, for anything matching that description.
But in fact category 3a also includes scenarios which are completely classical. At best, they have defined a class of prediction calculi which includes quantum mechanics as a special case, but then go on to claim that this definition is the whole story about QM.