Jokes helped make communism collapse. “Anekdoty” as they were termed, helped dispel the climate of fear and highlighted the backwardness and stagnation that were the hallmark of central planning and the police state. The best ones were about people like Brezhnev; few found Stalin a good subject for humour.
In the communist era, the countries of eastern and central Europe were run by tightly knit clans. Connections, particularly those of your parents, mattered more than ability. The same kind of people held the top jobs in the ruling party, in government, in media and in commerce and industry. One of the most potent fuels for the revolutions of 1989 was public discontent with this closed system and the unfairness and incompetence that went along with it.