From the end of WWII to the late 1980s, while the Soviet government continued censoring and filtering all works of art and letters before making them available to the public, the censorship had a rather different impact on different arts. Much as it harmed Russian letters, plenty of good Russian prose and poetry was nonetheless published in the USSR before 1953 and 1986. The selection of contemporary Russian music officially approved was poorer; but it was visual arts, and painting in particular, that underwent the most devastating pruning. Almost all talented painters were driven underground or out of the country.
Why? I’ll need a gallon of coffee to figure out, and a glass of whiskey to explain.
[August 4, 2019: I’m not sure anymore, especially of this: “plenty of good Russian prose and poetry was nonetheless published in the USSR before 1953 and 1986.” Some good prose and, occasionally, passable poetry – at best.]