1. I am not one to criticize people for doing what they must do to protect their lives and the lives of their families in a dictatorship.
2. I do not let the political, social, religious, sexual or psychological characteristics of a composer affect my judgment of their music.
So, judge the music of Khrennikov and Kabalevsky on the basis of their music. But I think the notion that these two fellows protected other composers from the state is very questionable. Whether he personally agreed with the condemnation of Shostakovich, Prokofiev, Khachaturian and Myaskovsky for "elitist, anti-socialist" music and "formalism," he was head of the witch hunt and he did nothing to stop it. I was particularly disturbed to learn of the actions of Kabalevsky. He was on the list at the beginning, but he convinced the council that he was not to blame, that he was under the spell of Myaskovsky, and that Myaskovsky should be condemned instead. This was after Myaskovsky had won the Stalin Prize, and was especially dispicable because Myaskovsky was Kabalevsky's teacher. And yes, you can hear the influences of Myaskovsky in the early music of Kabalevsky. After the reprieve, Kabalevsky wrote mostly children's music and (IMO) banal pieces of schlock.
It's true, Khrennikov did say in an interview, that he was required to read the speech attacking Shostakovich and Prokofiev in 1948: "What else could I have done? If I'd refused, it could have been curtains ... death. They made me do it; and anyway, Shostakovich and Prokofiev were sympathetic to my plight - they knew I had no choice: I did everything I could to help them financially while they were banned and repressed ... and they were grateful to me".
But then he went on to brag about how proud he was of the power he wielded under Stalin: "My word was law", he says. "People knew I was appointed personally by Stalin and they were afraid that ... I would go and tell Stalin about them. I was Stalin's Commissar. When I said No! (he shouts), it meant No." He explained how brave he was, that he would "argue with the Great Leader over the fate of musicians, defending the truly deserving among them and condemning those who fell short."
If Khrennikov had any regrets about his actions, he sure didn't let on. He remained the head of the council, passing judgment on the music of composers, until 1991. As is the case of all who have the power of life and death in a dictatorship, he was a tyrant himself.
This is largely irrelevant in the enjoyment of his music. And Kabalevsky was merely trying to save his own skin, tossing out a sick man as a substitute, Myaskovsky, who had led the Moscow Conservatory for decades and taught so many (including Khachaturian).
People do things in crisis that they would never do under other circumstances. I am unable to condemn them for their weakness. It was a different world, a different time. The same can be said of Wagner and Pfitzner and others who were products of their time and place.
Even so, although I can say good things about their music, I'm unable to say good things about the men.