Seems to me that he does say here, that life for Jews overall in the gulags was especially hard. (Or have my brain receptors failed me?) If he saw that things were different in those particular camps in which he was incarcerated, he did. Obviously by his earlier statement, he has no bone to pick, with Jews. Furthermore, by this statement and others he shows that generalizing is not his purpose.
Jesus was a Jew; so was Caiaphas. So were John the Baptist and Herod both, ethnically. David and Absalom? - Both of the tribe of Benjamin. Elijah was a descendent of Israel, so was Ahab. So what? So we're all human.
(Well, Jesus was also something more than that, but that's another matter. ;-` I'm just very glad myself, to be of "an engrafted branch.")
Here is the offending quote: "But in the camps where I was kept, it was different. The Jews whose experience I saw - their life was softer than that of others."
Apparently you know more about what Mr. Solzhenitsyn personally observed than he himself does?
Personally, I don't know whether I believe or disbelieve his claim. But it is, after all, an eyewitness testimony - which may or may not be a lie, or a false memory, or something. But the article tries to make it seem like he made the charge that all Jews in all camps had it easier, and from this quote I don't think that's true.