I don’t think officers got the service ribbon, so if you saw one on an officer you knew they were former enlisted. Which to me added a little more respect of them.
Perhaps. But when still in AIT we got a new butterbar, I don’t remember where he slotted in the CoC, but he looked about 16 years old and had That One Ribbon, and we were young-n-dumb enough to feel like we could get away with whistling the Andy Griffith Show theme whenever we saw him, and if he was former enlisted it had been for about six weeks :)
Officers receive the Army Service Ribbon on completion of their officer basic course. Officers are not awarded the Good Conduct Medal, or the NCO Professional Development Ribbon.