I have a little problem with not being able to fully and openly celebrate my birthday and that of my loved ones due to Biblical principles. Having said that, I have my own personal little rituals that celebrate my birthday privately, and I know of several JWs that have their own personal rituals to observe the special day in a private manner.
Then again, as big an Organization and as clicky as we all are, if we were to have birthday celebrations, we'd be celebrating each day, and yes, then it sure would be most distracting from what's really important in these difficult times: The preaching work.
DY