In vanilla Fallout 4, everything (weapons, armor, junk and enemies) level with the player to a certain degree. This means that certain enemies and weapons (like the Gauss Rifle) only appear if the player reached a certain level.

FROST changes this: Any enemy and item can be found at any level, and these things do not scale with the player's level anymore. To balance this, bad and previously low-level things are more common then good and previously high-level things. It is possible to get a 4-barrel missile launcher at level 1 in FROST for example. In order to balance this further, NPCs and weapons have been adjusted so that killing certain enemies is easier and more realistic.