Two people. Same world. Completely different realities. What the world calls daytime — the pursuit of pleasure, status, possessions — is darkness for the sage. And what the world sleeps through — the awareness of the Self, the silent truth beneath all movement — is precisely where the sage is wide awake.
This is not about literal day and night. It is about what you are awake to. Most people are awake to the external and asleep to the internal. The sage is the reverse. The same sun shines, but they are looking at different horizons.
There is no judgment in Krishna's words, only observation. He does not say the world is wrong to sleep or the sage is better for being awake. He simply describes two modes of consciousness — and leaves Arjuna to consider which one he wants to inhabit.