That's true about some people everywhere.
But what's also true is that, no matter how legitimate the criticism, or how dangerous the weakness, of a candidate, "many of the types who inhabit FR" refuse to engage it and instead blithely dismiss it with "No one's perfect."
The truth is that no one is perfect.
That doesn't mean we pretend everyone is equally imperfect (politically or personally), therefore any discussion of their imperfections is not necessary or relevant.
This is not the problem. The problem -- and it isn't exclusive to FR, or the Left/Right schism, or even to politics -- is that too many people leap all the way from "I don't agree with you" to "I seriously hate you because I don't agree with you" all in one short step. People become so caught up in their points of disagreement, they fail to appreciate the areas where they do agree, where there is plenty of common ground. Sticking to politics, there truly are plenty of people who claim to hate the Left, but for whom no Republican is ever good enough. So while they're looking for the impossible, the possible is seldom accomplished.