My hypothesis is no, they don’t. Certainly, I have not played in a game (or run one, tbh) in which the rules for perception have been followed as written. (I cannot think of a single time I have rolled Perception with disadvantage due to light levels alone.)
The rules I am thinking about involve the interaction of Darkvision, environmental lighting, and the Perception skill:
- Areas of dim light are lightly obscured, and give disadvantage on Wisdom (Perception) checks. [PHB 183]
- Darkvision lets you see in dim light as in bright light, and in darkness as if you were in dim light. [PHB 184-85, and relevant race entries]
- Therefore, anyone using Darkvision to see in the dark should make their Perception rolls with disadvantage (or have -5 to their passive perception).
...
What are your thoughts? Do you play RAW? How does it work out?