It’s the year of Luigi!

No, it is a simple recompile, from the original source code

Didn’t they use static recompilation?

The Xbox 360 uses a processor with a different instruction set which means the executable on the disc simply isn’t compatible with the Xbox One and Series X|S. For those, Microsoft have worked with game vendors to convert the executable (from binary, not source) to the other platform: “static recompilation”. The new executable must be downloaded to play the game.

For the Xbox One, the architecture is very similar to the Series X|S so it can mostly just run it like you can run Windows 7 games on Windows 11 with compatibility tweaks applied by the operating system.