The last one system update from Xbox Series X|S made it much easieremulation of the old gaming systems, because the new version of the Edge browser allows to overcome the problem of having to access the console in developer mode (which costs about 20 € to be unlocked) to run the emulators.
However, be careful, because the Xbox browser blocks access to files. Of course there is a way to get over the problem, but it’s not exactly spotless, so let’s avoid reporting it. We are for the legal emulation, the one made of ROMs of the games you own (there is a lot of free stuff around, just search).
Of course, the emulators developed specifically forhardware of Xbox remain better in terms of performance, especially for running newer system titles like PS2, GameCube, Nintendo Wii and Dreamcast.