Does a ROG Ally run virtually every game on an XBox Series X ... yes it does. Who cares if it "beats an XBox Series S!!!!". It plays every fucking game the Series S plays does it not? Forza? Runs. Starfield? It works fine. Halo? Of course. It even runs the hilariously poorly optimized Star Wars: Jedi Survivor which is a next-gen exclusive and it runs it fine.
For people who want to say "well dur hur!!! I don't like it cuz it's not the exact same performance, its not the same rezolution and framerate!", no shit Einstein. You can bring an XBox Series X with you in your carry on luggage and try to play it on an airplane and look like a idiot, the rest of us are fine playing on a ROG Ally or Steam Deck 2 or Switch 2.