At this point, traffic narrows to go over the bridge. Depending on traffic coming the other way, a bike rider or pedestrian may want to move near to where this sign is to give oncoming traffic a wide berth. (Pedestrian with dog, bike with trailer, drunk with attitude, etc.) This could easily cause an accident. Any sidewalk users could be affected, but it's obvious how this could be dangerous for a bike. The pole is hard to make out from the background, particularly on a cloudy day. Hanging up handlebars or a trailer on the poll could easily result in getting thrown from the bike, into bridge traffic.
It's a matter of time before something bad happens, and somebody rushes out to fix this.
[Update: I submitted this as an incident on Bikewise.org]