Developer Rocket League: Supporting 120fps on PS5 is more work than on Xbox – Gaming – News

Note; this is not completely correct.

The Xbox Series S / X also use a compatibility mode for the Xbox One games, but that is implemented completely differently than with PlayStation. With the PS5 you practically have a completely separate system that mimics the PS4, with the Xbox Series S / X there is only one system that limits what Xbox One games could do. Xbox One games could perform much better on the Series than they do now, but are currently being held back on it to avoid compatibility issues, but the Series is also able to push the limit of that compatibility mode for games that may handle more can.

As long as a game is developed with the Durango XDK it is subject to these limits unless that game has been given special exceptions by the OS. As soon as a game uses the Scarlett XDK (which can also be used for the One) all limits are dropped. But as you mentioned this is indeed native and not emulation in the Xbox’s case, but saying that the Series does not use any compatibility mode at all is also incorrect.

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