We should not forget that from an evolutionary perspective (if we regard groups as the players) it is advantageous to have at least some bias in favor of the group you belong to. Groups which don't do this, are out-competed by groups who do.
Of course, too much bias leads to extremism. However, no bias at all might lead to the extinction of the group in question.
I recently read an interesting article that touched on this The Three Lessons of Biological History which was extracted from The Lessons of History by Will and Ariel Durant. I believe this is what you are talking about, not the strictly biological perspective others are inferring.
This sort of thinking seems bad:
This sort of thinking seems socially frowned upon, but accurate:
Similar points could be made by replacing a/b with [group of people]. I think it's terrible to say something like:
But to me, it doesn't seem wrong to say something like:
Credit and accountability seem like good things to me, and so I want to live in a world where people/groups receive credit for good qualities, and are held accountable for bad qualities.
I'm not sure though. I could see that there are unintended consequences of such a world. For example, such "score keeping" could lead to contentiousness. And perhaps it's just something that we as a society (to generalize) can't handle, and thus shouldn't keep score.