mrunner
Well I just gave an example how borders and land control can be complicated. And given the fact that in this case two countries haven't resolved their border issues, it is in my opinion not to be bias and present both views. Isn't OSM trying to be neutral and supporting peace? Therefore if you present only one definition as definite border you are actually creating condition for rage debates of who is right which on platform like OSM isn't very useful for anyone. 

In fact in this particular case does not only consider two entities namely Croatia and Serbia, but there is also third party called Liberland which was crated on unclaimed land between those two lines. I understand there is unfriendly view on OSM towards non-fully unrecognised entities/countries which is somewhat understandable as it could also be seen as bias information to some. But in case of two UN members having dispute, there should have been no biased opinion, just facts presented as they are.

Maybe it would be best to erase all the borders from OSM in order not to offend someone, but if goal is to present facts, present all of them and not only some. 
My humble opinion.