They are trying to make Alyx work standalone: https://www.digitalfoundry.net/news/2025/11/valve-looking-into-a-steam-frame-half-life-alyx-standalone-experience
But that will probably be an exception due to the amount of resources Valve will invest into getting it to work well, you’re right that few other games on that level would run standalone.





Even for CPU-heavy titles it depends on the exact instructions. Sometimes multiple instructions in one architecture can be replaced by a single one in another. But that’s rare, on average performance will be negatively affected.