Rebar sticking up out of the bond beam is just fine. You cut off some and bend the rest of it over so it gets embedded in the coping mortar, which helps lock the coping to the wall. In some rare situations you bend it over so it gets embedded in the deck, but that is only for special situations where you need to lock the deck to the shell (which usually causes more problems than it solves).
The problem I see in your picture is that the rebar should be centered horizontally in the wall thickness. Instead, it is coming out of the very edge of the wall. If I am reading the picture correctly it is on the outside of the wall, away from the water, so rust shouldn't be a dramatic problem in the short run. However, rebar that close to the edge won't serve the structural purpose it is supposed to serve; which could dangerously weaken the wall. In places it also isn't really even sealed into the wall, which could lead to long term rusting out and eventual complete loss of the rebar.
The structural issues could be a major problem, depending on how much of the rebar is that close to the outside edge of the wall.