Three thousand Kelvin became a compromise so familiar that it began to pass as neutral. It is not neutral. It is a habit. In many northern interiors it is too clean to feel warm and too warm to feel clear. It often lands in the space between decisions.
I still use it. A station canopy with old brick may need exactly that temperature. A hotel corridor may use it well if the materials are doing other work. But I no longer start there. I start with the surfaces, the hour, the expected skin tones, the maintenance team, and the daylight that remains at the edge of the room.
The difference between 2700K and 3000K can be small on a schedule and large in a life. A winter reading room at 16:00 may need warmth because the body is already reading the day as over. A civic underpass may need warmth because recognition is easier when faces are not flattened by a cold source.
Standards are useful when they keep us honest. They are dangerous when they keep us asleep. Color temperature should be a consequence, not a default.