Yes... that is why I divided by area.
It's kind of sad how many of us end up so impatient over common mistakes that we screw up just as badly in our eagerness to snap at people.
Obviously it's fudged a bit. The LED is not an isotropic emitter, and it's not at the center of a spherical room with perfectly reflective walls.
In practice, I suspect the amount of blue illumination from one dim blue LED in a large bedroom and the night sky are pretty much equal.
