This is the normal thing, or has been for hundreds, thousands of years. People are loyal to some institutions - nowadays a political party or ideology; at other times to a denominational church, a nation or town, a guild or trades union...
And they are against the others.
The underlying assumption of institutional partisanship is that we are well-motivated, they are not.
We make mistakes, they do bad things because it is their nature. We are overall good and tending to good; their flaws and sins made their evil inevitable.
And so on. But this attitudes has become impossible for some, and is becoming more so for more. It is a matter of honesty.
Whether because of the corruption of institutions, which is now so obvious as to be ignore-able only by self-blinding; or whether (as I think) because the development of human consciousness; the effect is that we can no longer regard institutions (not even churches) as well - or badly-motivated, but only specific people.
We used to naturally regard institutions as persons, capable of moral life, like human persons; now, we can't honestly make ourselves believe it. A bureaucracy cannot truly be regarded as a person! (Not even when it is a church.)
No longer can we ally in institutions, because we know we will be betrayed (or will betray). We can ally with individuals, and on the basis of what we discern of their hearts. But these allies will come from all over the place, will hold a variety of specific convictions.
Our friends will specifically be chosen on what we infer of their character, and not by virtue of membership.