There is backward compatibility as a cornerstore feature on next-gen Xbox Series X/S consoles. Even though backward compatibility a key feature, making PS2 games playable on Xbox Series X/S wasn’t one of the intentions of Xbox.
According to Youtuber “Modern Vintage Gamer”, caused by a loophole, developer mode on Xbox Series X/S lets users boot up a variety of emulators. Including ones that can launch PS2, Wii, Dreamcast, and GameCube games.
Modern Vintage Gamer ran tests on Series S, playing PS2 games such as God of War, Silent Hill 2, Metal Gear Solid 2, and more, through RetroArch emulator.
Even though it’s not official, Xbox Series S/X can play more PS2 games than PS5, which can only play PS3 and PS4 games through PS Now.