No it doesn't seem fair and personally I think evil and suffering are the most powerful arguments for a materialistic /atheistist worldview. If suffering is part of 'collective growth' then each individual life is meaningless and Alex goes on repeatedly that he does not belive we are biological robots living a meaningless life in a meaningless universe but if an individual life of suffering only has meaning as a part of collective growth then I don’t think that is real meaning.
But that experience has a lot to do with the person I am today. I met people who I'd never have met otherwise, and I wouldn't give up those relationships for a way to undo the accident. I learned so much because of that accident. I'm a better person. Given the choice, I wouldn't change what happened to me.