In the recent lawsuit against Google, Epic Games revealed to the outside world that the main reason why they cannot lower the prices of games such as "Fortnite" is that they have reached an agreement with Sony for PlayStation. Epic CEO Tim Sweeney said in response: "We can't sell games outside of the PlayStation platform at a lower price than the PlayStation platform." This is due to a "most favored nation" clause in their deal with Sony, which restricts Epic from offering games at different prices to customers who are not on PlayStation.
According to Sweeney, this is standard for all PlayStation contracts and has nothing to do with the fact that Sony is an Epic Games shareholder. Regardless of whether there is any doubt, this is the real reason why the prices of games on different platforms cannot be synchronized so far.