In a memoir of his experiences during World War II in the Red Army, author Nikolai Nikulin said that Joseph Stalin was a far removed, mysterious figure in Russia, similar to the Wizard of Oz. Is this an accurate representation of how Russians would've viewed him?

Other sources seem to suggest a similar perception of Stalin, and not only during the Great Patriotic War.

Throughout the Yezhovshchina from 36-38, and indeed in relation to any kind of purging or extra-judiciary punishment from the secret police, there was a mentality that these problems were localised systemic problems which Stalin would have fixed if only he knew they were taking place. This is a result of propaganda glorifying Stalin and a lack of awareness that these problems were, in fact, taking place across the USSR. Back then, especially given the size of the USSR, people in Kiev, for example, had no clue what was going on in Moscow, let alone Vladivostok.

I came across another instance of the mentality you describe in Aleksandr Solzhenitsyn's book "One Day in the Life of Ivan Denisovich" (a great read) which basically describes a day in the life of a Gulag prisoner. In it, if memory serves me well, Stalin is venerated as a God by prisoners despite the fact that they have been thrown into the Gulag for ridiculous reasons. Once again, the prisoners prefer to believe that the injustice that has befallen them is a blip in the system rather than the norm, and that if Stalin was made aware, he would have fixed it. Ofcourse, in reality, it was Stalin himself who decided to lock up millions of POWs after the war. It's true that perhaps the experience of a Gulag prisoner are not representative of the general public of the USSR, but given that there were, at its peak, 10 million in the Gulag system under Stalin, their perspective represents a large chunk of the Soviet population.