it depends how you define an exploit, you both are thinking in a grand scheme - where it is not an exploit as it doesn¨t violate any rules. But you can look at it differently.
I am relatively new player so I might not know the history and all. But, I suspect that CCP never actually stated why it works the way it works, correct? And they did not change this mechanic despite it being abused by players in any way - which implies it is absolutely intented. Because of this it is understandable that you don’t see it as an exploit or anything wrong.
But lets apply common sense. What would be the reason for CONCORD not despawning? Because I see only one such reason and that is to prevent a gank on a same place. The only other explanation for this behavior is that it is either a bug or an oversight. Assuming the intent is to prevent gankers gank at the same place, pulling the CONCORD away from that spot would be an exploit to that. Especially when you can do it without ganking anyone just by jumping into rookie ships and undocking in mass. This is still perfectly legit and allowed as CCP didn’t made any actions against players doing it nor they change it - but I just cannot shake the feel of an exploit here.
I am maintaining and developing NWN1 game server so I believe I kind of understand what is and exploit and what is not. It is all about definition of the exploit. Your definition of what is exploit is slightly different than mine.
Either way. Lets not get mad at me for using the forbidden word in gankers community. What we do is not against rules and I never said the opposite.