This article analyses one of the trials aiming to bridge the incommensurability gap between special relativity and quantum mechanics in the form of postulating the quantum principle of relativity. The postulate is argued here to be rather a conventionalist stratagem than a new paradigm in theoretical physics. It is worth emphasising this claim does not assess the scientific value of the analysed work at all. Moreover, I draw attention to favouring both the mathematical instrumentalism and the ontic character of probability in the article in question.