Your knowledge of that era seems to be lacking
Before you start lecturing me about Polish culture, which I find quite amusing :-), first you have to get familiar with what
socialist realism was and in which era it was the most active and the most influential style in Poland.
That would be the period from right after WWII to 1956, that is to Polish Thaw. So for over 10 years no work of art which contradicted socialist realism was allowed. That's hardly an environment for an independent artist.
During that time a Polish future nobelist Czeslaw Milosz defected to the US and wrote his best novel which describes a communist totalitarian mind control "The Captive Mind". Czeslaw Milosz was banned [censored] in People's Republic until winning his nobel prize in 1980 when commies could no longer deny his existence and his talent.
After 1956 the freedom of artistic expression has widened [but was still not very vast] until the collapse of a communist block. Yet up until 1989 every major work of art such as film had to be approved by the office of censorship and obviously financed by the government since there were no private film or recording studios in Poland back then.
Was any significant work of art created after 1956? Yes, plenty, but it had to be apolitical.
Artist were not allowed to criticize communist party and communism as a whole and even a
sensitive historical subjects, such as past Russo-Polish affairs were heavily censored or completely banned. Historical works of Polish nobelist Sienkiewicz, such as With Sword and Fire, comes in mind .
en.wikipedia.org/wiki/Socialist_realism
Socialist realism never really took off in Poland.
It didn't took off in minds of most of the Poles yet it was officially enforced on Poland, and this ugly building founded by Stalin himself is one of the most visible signs of it.
pl.wikipedia.org/wiki/Socrealizm