There’s grey area. For example: Half Life 2. Every so often there’s a downtime area full of boxes. The amount of loot in those boxes is enough to get your ammo

There’s grey area. For example: Half Life 2. Every so often there’s a downtime area full of boxes. The amount of loot in those boxes is enough to get your ammo up to the levels the game thinks you need for the next challenge. Is this dynamic difficulty? Depends on how you view it. The worse you were at the previous section, the better your rewards, but maybe the challenge is just “get to the next area by any means necessary”. Either way it’s pretty invisible to the player.