With the way they reused, dynamically loaded assets before and tried to keep world seamless, they'd probably load\unload parts of these 125 Gb a lot, with this 16 Gb RAM requirement no less. They test it with SSD and make it so it doesn't have microstutter and loading problems on their target machine. Or, god forbid, loading screens when walking outside, like it was in TES3; or TES4 banning levitation and loading complex cities as different locations that won't work in a space sim etc etc. BethSoft had many problems with it already. I doubt it'd refuse to work, but if they build their game around it, the result is unpredictable. Bet, it'd load low-res LOD textures and only then replace them with okay ones. That'd probably ruin the spaceship landing – one of the, possibly, most demanding and visually sweet parts of the game. It looking great is their baseline here.