Comment by adammarples

These seem to be more bugs than features of the totalitarian regime. A couple of illustrative points from Lem's Wikipedia page:

After the 1939 Soviet occupation of western Ukraine and Belarus, he was not allowed to study at Lwow Polytechnic as he wished because of his "bourgeois origin"

"During the era of Stalinism in Poland, which had begun in the late 1940s, all published works had to be directly approved by the state.[23] Thus The Astronauts was not, in fact, the first novel Lem finished, just the first that made it past the state censors"

"most of Lem's works published in the 1950s also contain various elements of socialist realism as well as of the "glorious future of communism" forced upon him by the censors and editors. Lem later criticized several of his early pieces as compromised by the ideological pressure"

"Lem became truly productive after 1956, when the de-Stalinization period in the Soviet Union led to the "Polish October", when Poland experienced an increase in freedom of speech"