Value of LED current limiting resistor incorrect?
They’re choosing to drive the LED at about 1.5mA, which may be bright enough for their application, especially if the LED is high efficiency.

Rarely is it useful (or wise) to drive an indicator LED at its max rated current. Beyond a certain point the LED doesn’t appear much brighter, given the eye’s logarithmic response to light, so you’re shedding all that power in the LED for nothing.