That’s not the case. The game folder is accessible… Game pass has been doing that at least since its had Bethesda games on the service.

That being said, the exe is technically different from Steam so the script extender doesn’t work. Not actually a big issue this early in the mod scene (most mods don’t use the script extender yet). That won’t be the case forever unfortunately.

Source: I have the game pass version and have been installing mods just like I would with the Steam version of Skyrim and Fallout via Vortex