I would say probably more 451 games (essentially synonymous with Immersive Sims) where there's almost always a door with the code 0451, a reference to System Shock, where the first door uses this code as a reference to Fahrenheit 451. In the end you're right, but it's more a reference to this repeated reference (which is in itself a reference) than a reference to the book itself.
Also it's the first code entered into the first door to leave the first room in the first System Shock, which is likely what thread OP was referring to.
SS did it and so a bunch of other games do it in reference, like BioShock