Solzhenitsyn in particular is a political writer/figure who largely overshadows in the West other Soviet dissidents. His (put mildly) ethnocentrism discredits the overall message and makes him unsuitable champion of their case.
I'm not sure what that has to do with anything. He isn't a champion of whatever, and nobody is trying to make him one. He's a dead author, that's it. This isn't a religious movement or something, it is people liking a book. People liked a book, then you said they aren't allowed to like it because you used one of the progressive thought terminating cliches.