Share 'Passing other cyclists'

Is there a reason that no one ever says "on your left" anymore? I was actually called out for not doing so by a messenger about 3 weeks ago passing him on his left over the brigde heading southbound on Milwaukee, just before Grand/Halsted. I was embarassed but realized that no matter how close or far (I thought I left plenty of room for him to swerve) you are to someone it helps/doesn't hurt to l…